1218720 has 48 divisors (see below), whose sum is σ = 3840480. Its totient is φ = 324864.

The previous prime is 1218709. The next prime is 1218727. The reversal of 1218720 is 278121.

It is a tau number, because it is divible by the number of its divisors (48).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1218727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 790 + ... + 1749.

It is an arithmetic number, because the mean of its divisors is an integer number (80010).

2^1218720 is an apocalyptic number.

1218720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1218720 is an abundant number, since it is smaller than the sum of its proper divisors (2621760).

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

1218720 is a wasteful number, since it uses less digits than its factorization.

1218720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2557 (or 2549 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 21.

The square root of 1218720 is about 1103.9565208830. The cubic root of 1218720 is about 106.8155905924.

The spelling of 1218720 in words is "one million, two hundred eighteen thousand, seven hundred twenty".