121387342815 has 24 divisors (see below), whose sum is σ = 216091344768. Its totient is φ = 62990187840.

The previous prime is 121387342807. The next prime is 121387342829. The reversal of 121387342815 is 518243783121.

121387342815 is a `hidden beast` number, since 1 + 213 + 8 + 7 + 3 + 428 + 1 + 5 = 666.

It is not a de Polignac number, because 121387342815 - 2³ = 121387342807 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36450991 + ... + 36454320.

It is an arithmetic number, because the mean of its divisors is an integer number (9003806032).

Almost surely, 2^121387342815 is an apocalyptic number.

121387342815 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

121387342815 is a deficient number, since it is larger than the sum of its proper divisors (94704001953).

121387342815 is a wasteful number, since it uses less digits than its factorization.

121387342815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72905359 (or 72905356 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The spelling of 121387342815 in words is "one hundred twenty-one billion, three hundred eighty-seven million, three hundred forty-two thousand, eight hundred fifteen".