121664615 has 16 divisors (see below), whose sum is σ = 151818240. Its totient is φ = 93497760.

The previous prime is 121664591. The next prime is 121664633. The reversal of 121664615 is 516466121.

It is not a de Polignac number, because 121664615 - 2²⁰ = 120616039 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18722 + ... + 24368.

It is an arithmetic number, because the mean of its divisors is an integer number (9488640).

Almost surely, 2^121664615 is an apocalyptic number.

121664615 is a deficient number, since it is larger than the sum of its proper divisors (30153625).

121664615 is a wasteful number, since it uses less digits than its factorization.

121664615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5822.

The product of its digits is 8640, while the sum is 32.

The square root of 121664615 is about 11030.1684030662. The cubic root of 121664615 is about 495.5126681831.

The spelling of 121664615 in words is "one hundred twenty-one million, six hundred sixty-four thousand, six hundred fifteen".