121905920 has 36 divisors (see below), whose sum is σ = 292005840. Its totient is φ = 48761856.

The previous prime is 121905913. The next prime is 121905923. The reversal of 121905920 is 29509121.

It is a super-2 number, since 2×121905920² = 29722106662092800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (121905923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46340 + ... + 48899.

Almost surely, 2^121905920 is an apocalyptic number.

121905920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121905920 is an abundant number, since it is smaller than the sum of its proper divisors (170099920).

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

121905920 is an frugal number, since it uses more digits than its factorization.

121905920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95260 (or 95246 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 121905920 is about 11041.1013943356. The cubic root of 121905920 is about 495.8400455431.

The spelling of 121905920 in words is "one hundred twenty-one million, nine hundred five thousand, nine hundred twenty".