1218640572 has 24 divisors (see below), whose sum is σ = 3159438800. Its totient is φ = 406213488.

The previous prime is 1218640571. The next prime is 1218640589. The reversal of 1218640572 is 2750468121.

1218640572 is a `hidden beast` number, since 1 + 2 + 1 + 8 + 640 + 5 + 7 + 2 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218640571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5641747 + ... + 5641962.

Almost surely, 2^1218640572 is an apocalyptic number.

1218640572 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1218640572 is an abundant number, since it is smaller than the sum of its proper divisors (1940798228).

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

1218640572 is a wasteful number, since it uses less digits than its factorization.

1218640572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11283722 (or 11283714 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 1218640572 is about 34909.0328138721. The cubic root of 1218640572 is about 1068.1327003398.

The spelling of 1218640572 in words is "one billion, two hundred eighteen million, six hundred forty thousand, five hundred seventy-two".