21165150618 has 24 divisors (see below), whose sum is σ = 45964241856. Its totient is φ = 7038678600.

The previous prime is 21165150599. The next prime is 21165150641. The reversal of 21165150618 is 81605156112.

21165150618 is a `hidden beast` number, since 21 + 1 + 6 + 5 + 15 + 0 + 618 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1356328 + ... + 1371843.

It is an arithmetic number, because the mean of its divisors is an integer number (1915176744).

Almost surely, 2^21165150618 is an apocalyptic number.

21165150618 is an abundant number, since it is smaller than the sum of its proper divisors (24799091238).

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

21165150618 is a wasteful number, since it uses less digits than its factorization.

21165150618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2728610 (or 2728607 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 36.

The spelling of 21165150618 in words is "twenty-one billion, one hundred sixty-five million, one hundred fifty thousand, six hundred eighteen".