121257621 has 16 divisors (see below), whose sum is σ = 184497600. Its totient is φ = 78652944.

The previous prime is 121257611. The next prime is 121257641. The reversal of 121257621 is 126752121.

121257621 is a `hidden beast` number, since 12 + 1 + 25 + 7 + 621 = 666.

It is not a de Polignac number, because 121257621 - 2⁵ = 121257589 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121257611) 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, 59691 + ... + 61688.

It is an arithmetic number, because the mean of its divisors is an integer number (11531100).

Almost surely, 2^121257621 is an apocalyptic number.

It is an amenable number.

121257621 is a deficient number, since it is larger than the sum of its proper divisors (63239979).

121257621 is a wasteful number, since it uses less digits than its factorization.

121257621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121425 (or 121419 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 121257621 is about 11011.7038191190. The cubic root of 121257621 is about 494.9595191873.

The spelling of 121257621 in words is "one hundred twenty-one million, two hundred fifty-seven thousand, six hundred twenty-one".