121564640 has 48 divisors (see below), whose sum is σ = 296472960. Its totient is φ = 47055360.

The previous prime is 121564633. The next prime is 121564673. The reversal of 121564640 is 46465121.

121564640 = T₂₇₈₅ + T₂₇₈₆ + ... + T₂₈₁₅.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7295 + ... + 17214.

It is an arithmetic number, because the mean of its divisors is an integer number (6176520).

Almost surely, 2^121564640 is an apocalyptic number.

121564640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121564640 is an abundant number, since it is smaller than the sum of its proper divisors (174908320).

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

121564640 is a wasteful number, since it uses less digits than its factorization.

121564640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24555 (or 24547 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 121564640 is about 11025.6355825866. The cubic root of 121564640 is about 495.3769057449.

The spelling of 121564640 in words is "one hundred twenty-one million, five hundred sixty-four thousand, six hundred forty".