121901815 has 64 divisors (see below), whose sum is σ = 191600640. Its totient is φ = 72437760.

The previous prime is 121901809. The next prime is 121901831. The reversal of 121901815 is 518109121.

It is not a de Polignac number, because 121901815 - 2³ = 121901807 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 463374 + ... + 463636.

It is an arithmetic number, because the mean of its divisors is an integer number (2993760).

Almost surely, 2^121901815 is an apocalyptic number.

121901815 is a deficient number, since it is larger than the sum of its proper divisors (69698825).

121901815 is a wasteful number, since it uses less digits than its factorization.

121901815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352.

The product of its (nonzero) digits is 720, while the sum is 28.

The square root of 121901815 is about 11040.9154964613. The cubic root of 121901815 is about 495.8344799227.

The spelling of 121901815 in words is "one hundred twenty-one million, nine hundred one thousand, eight hundred fifteen".