21612112055265 has 16 divisors (see below), whose sum is σ = 35771771678400. Its totient is φ = 11128995632832.

The previous prime is 21612112055239. The next prime is 21612112055327. The reversal of 21612112055265 is 56255021121612.

It is a happy number.

It is not a de Polignac number, because 21612112055265 - 2¹³ = 21612112047073 is a prime.

It is a Curzon 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, 24841507675 + ... + 24841508544.

It is an arithmetic number, because the mean of its divisors is an integer number (2235735729900).

Almost surely, 2^{21612112055265} is an apocalyptic number.

It is an amenable number.

21612112055265 is a deficient number, since it is larger than the sum of its proper divisors (14159659623135).

21612112055265 is a wasteful number, since it uses less digits than its factorization.

21612112055265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49683016256.

The product of its (nonzero) digits is 72000, while the sum is 39.

Adding to 21612112055265 its reverse (56255021121612), we get a palindrome (77867133176877).

The spelling of 21612112055265 in words is "twenty-one trillion, six hundred twelve billion, one hundred twelve million, fifty-five thousand, two hundred sixty-five".