21120646215525 has 48 divisors (see below), whose sum is σ = 35033443162560. Its totient is φ = 11227583577600.

The previous prime is 21120646215511. The next prime is 21120646215707. The reversal of 21120646215525 is 52551264602112.

It is not a de Polignac number, because 21120646215525 - 2⁷ = 21120646215397 is a prime.

It is a super-2 number, since 2×21120646215525² (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, 546736911 + ... + 546775539.

It is an arithmetic number, because the mean of its divisors is an integer number (729863399220).

Almost surely, 2^{21120646215525} is an apocalyptic number.

21120646215525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21120646215525 is a deficient number, since it is larger than the sum of its proper divisors (13912796947035).

21120646215525 is a wasteful number, since it uses less digits than its factorization.

21120646215525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62246 (or 62241 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 42.

The spelling of 21120646215525 in words is "twenty-one trillion, one hundred twenty billion, six hundred forty-six million, two hundred fifteen thousand, five hundred twenty-five".