121839238521 has 96 divisors (see below), whose sum is σ = 240753606912. Its totient is φ = 57321838080.

The previous prime is 121839238487. The next prime is 121839238567. The reversal of 121839238521 is 125832938121.

121839238521 is a `hidden beast` number, since 1 + 2 + 1 + 8 + 3 + 92 + 38 + 521 = 666.

It is not a de Polignac number, because 121839238521 - 2⁶ = 121839238457 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121839238121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 349891 + ... + 605063.

It is an arithmetic number, because the mean of its divisors is an integer number (2507850072).

Almost surely, 2^121839238521 is an apocalyptic number.

121839238521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121839238521 is a deficient number, since it is larger than the sum of its proper divisors (118914368391).

121839238521 is a wasteful number, since it uses less digits than its factorization.

121839238521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255263 (or 255260 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The spelling of 121839238521 in words is "one hundred twenty-one billion, eight hundred thirty-nine million, two hundred thirty-eight thousand, five hundred twenty-one".