121559431 has 4 divisors (see below), whose sum is σ = 138925072. Its totient is φ = 104193792.

The previous prime is 121559429. The next prime is 121559443. The reversal of 121559431 is 134955121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 121559431 - 2¹ = 121559429 is a prime.

It is a super-2 number, since 2×121559431² = 29553390530087522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121559393 and 121559402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121559491) 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, 8682810 + ... + 8682823.

It is an arithmetic number, because the mean of its divisors is an integer number (34731268).

Almost surely, 2^121559431 is an apocalyptic number.

121559431 is a deficient number, since it is larger than the sum of its proper divisors (17365641).

121559431 is an equidigital number, since it uses as much as digits as its factorization.

121559431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17365640.

The product of its digits is 5400, while the sum is 31.

The square root of 121559431 is about 11025.3993578464. The cubic root of 121559431 is about 495.3698300712.

The spelling of 121559431 in words is "one hundred twenty-one million, five hundred fifty-nine thousand, four hundred thirty-one".