21221365113525 has 48 divisors (see below), whose sum is σ = 35172371949120. Its totient is φ = 11290201036800.

The previous prime is 21221365113469. The next prime is 21221365113581. The reversal of 21221365113525 is 52531156312212.

It is an interprime number because it is at equal distance from previous prime (21221365113469) and next prime (21221365113581).

It is not a de Polignac number, because 21221365113525 - 2¹² = 21221365109429 is a prime.

It is a super-2 number, since 2×21221365113525² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 502747621 + ... + 502789829.

It is an arithmetic number, because the mean of its divisors is an integer number (732757748940).

Almost surely, 2^{21221365113525} is an apocalyptic number.

21221365113525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21221365113525 is a deficient number, since it is larger than the sum of its proper divisors (13951006835595).

21221365113525 is a wasteful number, since it uses less digits than its factorization.

21221365113525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58566 (or 58561 counting only the distinct ones).

The product of its digits is 108000, while the sum is 39.

The spelling of 21221365113525 in words is "twenty-one trillion, two hundred twenty-one billion, three hundred sixty-five million, one hundred thirteen thousand, five hundred twenty-five".