21122517265 has 32 divisors (see below), whose sum is σ = 27425664000. Its totient is φ = 15562637568.

The previous prime is 21122517259. The next prime is 21122517271. The reversal of 21122517265 is 56271522112.

It is an interprime number because it is at equal distance from previous prime (21122517259) and next prime (21122517271).

It is a cyclic number.

It is not a de Polignac number, because 21122517265 - 2³ = 21122517257 is a prime.

It is a super-2 number, since 2×21122517265² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21122517265.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6286656 + ... + 6290014.

It is an arithmetic number, because the mean of its divisors is an integer number (857052000).

Almost surely, 2^21122517265 is an apocalyptic number.

It is an amenable number.

21122517265 is a deficient number, since it is larger than the sum of its proper divisors (6303146735).

21122517265 is a wasteful number, since it uses less digits than its factorization.

21122517265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5209.

The product of its digits is 16800, while the sum is 34.

The spelling of 21122517265 in words is "twenty-one billion, one hundred twenty-two million, five hundred seventeen thousand, two hundred sixty-five".