21975012120 has 64 divisors (see below), whose sum is σ = 65968045920. Its totient is φ = 5856180224.

The previous prime is 21975012119. The next prime is 21975012121. The reversal of 21975012120 is 2121057912.

It is an interprime number because it is at equal distance from previous prime (21975012119) and next prime (21975012121).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21975012121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127402 + ... + 245318.

Almost surely, 2^21975012120 is an apocalyptic number.

21975012120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21975012120 is an abundant number, since it is smaller than the sum of its proper divisors (43993033800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21975012120 is a wasteful number, since it uses less digits than its factorization.

21975012120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119484 (or 119480 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 30.

The spelling of 21975012120 in words is "twenty-one billion, nine hundred seventy-five million, twelve thousand, one hundred twenty".