121515889 has 4 divisors (see below), whose sum is σ = 132562800. Its totient is φ = 110468980.

The previous prime is 121515857. The next prime is 121515913. The reversal of 121515889 is 988515121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 121515889 - 2⁵ = 121515857 is a prime.

It is a super-2 number, since 2×121515889² = 29532222558920642, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121515839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5523439 + ... + 5523460.

It is an arithmetic number, because the mean of its divisors is an integer number (33140700).

Almost surely, 2^121515889 is an apocalyptic number.

It is an amenable number.

121515889 is a deficient number, since it is larger than the sum of its proper divisors (11046911).

121515889 is a wasteful number, since it uses less digits than its factorization.

121515889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11046910.

The product of its digits is 28800, while the sum is 40.

The square root of 121515889 is about 11023.4245586388. The cubic root of 121515889 is about 495.3106766491.

The spelling of 121515889 in words is "one hundred twenty-one million, five hundred fifteen thousand, eight hundred eighty-nine".