21660502908929 has 16 divisors (see below), whose sum is σ = 24142013553600. Its totient is φ = 19313168338944.

The previous prime is 21660502908899. The next prime is 21660502908953. The reversal of 21660502908929 is 92980920506612.

It is a cyclic number.

It is not a de Polignac number, because 21660502908929 - 2³² = 21656207941633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21660502901929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32100782 + ... + 32768600.

It is an arithmetic number, because the mean of its divisors is an integer number (1508875847100).

Almost surely, 2^{21660502908929} is an apocalyptic number.

It is an amenable number.

21660502908929 is a deficient number, since it is larger than the sum of its proper divisors (2481510644671).

21660502908929 is a wasteful number, since it uses less digits than its factorization.

21660502908929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 768272.

The product of its (nonzero) digits is 8398080, while the sum is 59.

The spelling of 21660502908929 in words is "twenty-one trillion, six hundred sixty billion, five hundred two million, nine hundred eight thousand, nine hundred twenty-nine".