21534630026165 has 16 divisors (see below), whose sum is σ = 26755744267776. Its totient is φ = 16621603099200.

The previous prime is 21534630026159. The next prime is 21534630026209. The reversal of 21534630026165 is 56162003643512.

It is not a de Polignac number, because 21534630026165 - 2¹² = 21534630022069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 209817422 + ... + 209920031.

It is an arithmetic number, because the mean of its divisors is an integer number (1672234016736).

Almost surely, 2^{21534630026165} is an apocalyptic number.

It is an amenable number.

21534630026165 is a deficient number, since it is larger than the sum of its proper divisors (5221114241611).

21534630026165 is a wasteful number, since it uses less digits than its factorization.

21534630026165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 419737820.

The product of its (nonzero) digits is 777600, while the sum is 44.

Adding to 21534630026165 its reverse (56162003643512), we get a palindrome (77696633669677).

The spelling of 21534630026165 in words is "twenty-one trillion, five hundred thirty-four billion, six hundred thirty million, twenty-six thousand, one hundred sixty-five".