1218149604 has 135 divisors (see below), whose sum is σ = 3717820953. Its totient is φ = 346786272.

The previous prime is 1218149573. The next prime is 1218149609. The reversal of 1218149604 is 4069418121.

The square root of 1218149604 is 34902.

It is a perfect power (a square), and thus also a powerful number.

1218149604 is a `hidden beast` number, since 1 + 2 + 1 + 8 + 1 + 49 + 604 = 666.

1218149604 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 209960100 + 1008189504 = 14490^2 + 31752^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1218149609) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 4397514 + ... + 4397790.

Almost surely, 2^1218149604 is an apocalyptic number.

1218149604 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1218149604 is the 34902-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1218149604

1218149604 is an abundant number, since it is smaller than the sum of its proper divisors (2499671349).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1218149604 is an equidigital number, since it uses as much as digits as its factorization.

1218149604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 584 (or 289 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The cubic root of 1218149604 is about 1067.9892373616.

Multiplying 1218149604 by its sum of digits (36), we get a square (43853385744 = 209412²).

1218149604 divided by its sum of digits (36) gives a square (33837489 = 5817²).

The spelling of 1218149604 in words is "one billion, two hundred eighteen million, one hundred forty-nine thousand, six hundred four".