21052313555 has 64 divisors (see below), whose sum is σ = 31972147200. Its totient is φ = 12952410624.

The previous prime is 21052313551. The next prime is 21052313573. The reversal of 21052313555 is 55531325012.

It is a cyclic number.

It is not a de Polignac number, because 21052313555 - 2² = 21052313551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21052313551) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3183062 + ... + 3189668.

It is an arithmetic number, because the mean of its divisors is an integer number (499564800).

Almost surely, 2^21052313555 is an apocalyptic number.

21052313555 is a deficient number, since it is larger than the sum of its proper divisors (10919833645).

21052313555 is a wasteful number, since it uses less digits than its factorization.

21052313555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6828.

The product of its (nonzero) digits is 22500, while the sum is 32.

Adding to 21052313555 its reverse (55531325012), we get a palindrome (76583638567).

The spelling of 21052313555 in words is "twenty-one billion, fifty-two million, three hundred thirteen thousand, five hundred fifty-five".