21653051452564 has 36 divisors (see below), whose sum is σ = 44080195805184. Its totient is φ = 9279717165936.

The previous prime is 21653051452523. The next prime is 21653051452573. The reversal of 21653051452564 is 46525415035612.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10645357 + ... + 12515179.

Almost surely, 2^{21653051452564} is an apocalyptic number.

It is an amenable number.

21653051452564 is an abundant number, since it is smaller than the sum of its proper divisors (22427144352620).

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

21653051452564 is a wasteful number, since it uses less digits than its factorization.

21653051452564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1928924 (or 1928915 counting only the distinct ones).

The product of its (nonzero) digits is 4320000, while the sum is 49.

The spelling of 21653051452564 in words is "twenty-one trillion, six hundred fifty-three billion, fifty-one million, four hundred fifty-two thousand, five hundred sixty-four".