121925921 has 32 divisors (see below), whose sum is σ = 147329280. Its totient is φ = 100100352.

The previous prime is 121925911. The next prime is 121925927. The reversal of 121925921 is 129529121.

It is not a de Polignac number, because 121925921 - 2²² = 117731617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121925927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1468946 + ... + 1469028.

It is an arithmetic number, because the mean of its divisors is an integer number (4604040).

Almost surely, 2^121925921 is an apocalyptic number.

It is an amenable number.

121925921 is a deficient number, since it is larger than the sum of its proper divisors (25403359).

121925921 is an equidigital number, since it uses as much as digits as its factorization.

121925921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170 (or 136 counting only the distinct ones).

The product of its digits is 3240, while the sum is 32.

The square root of 121925921 is about 11042.0071092171. The cubic root of 121925921 is about 495.8671614109.

The spelling of 121925921 in words is "one hundred twenty-one million, nine hundred twenty-five thousand, nine hundred twenty-one".