121987239 has 48 divisors (see below), whose sum is σ = 196627200. Its totient is φ = 66908160.

The previous prime is 121987219. The next prime is 121987249. The reversal of 121987239 is 932789121.

It is not a de Polignac number, because 121987239 - 2⁷ = 121987111 is a prime.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 121987239.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121987219) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 158247 + ... + 159015.

It is an arithmetic number, because the mean of its divisors is an integer number (4096400).

Almost surely, 2^121987239 is an apocalyptic number.

121987239 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

121987239 is a deficient number, since it is larger than the sum of its proper divisors (74639961).

121987239 is a wasteful number, since it uses less digits than its factorization.

121987239 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 836 (or 825 counting only the distinct ones).

The product of its digits is 54432, while the sum is 42.

The square root of 121987239 is about 11044.7833387532. The cubic root of 121987239 is about 495.9502733165.

The spelling of 121987239 in words is "one hundred twenty-one million, nine hundred eighty-seven thousand, two hundred thirty-nine".