21530514155 has 32 divisors (see below), whose sum is σ = 26475724800. Its totient is φ = 16804961920.

The previous prime is 21530514149. The next prime is 21530514179. The reversal of 21530514155 is 55141503512.

It is not a de Polignac number, because 21530514155 - 2²² = 21526319851 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11809574 + ... + 11811396.

It is an arithmetic number, because the mean of its divisors is an integer number (827366400).

Almost surely, 2^21530514155 is an apocalyptic number.

21530514155 is a deficient number, since it is larger than the sum of its proper divisors (4945210645).

21530514155 is a wasteful number, since it uses less digits than its factorization.

21530514155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2251.

The product of its (nonzero) digits is 15000, while the sum is 32.

The spelling of 21530514155 in words is "twenty-one billion, five hundred thirty million, five hundred fourteen thousand, one hundred fifty-five".