51157121 has 4 divisors (see below), whose sum is σ = 51684612. Its totient is φ = 50629632.

The previous prime is 51157091. The next prime is 51157123. The reversal of 51157121 is 12175115.

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

It can be written as a sum of positive squares in 2 ways, for example, as 34058896 + 17098225 = 5836^2 + 4135^2 .

It is a cyclic number.

It is not a de Polignac number, because 51157121 - 2¹⁰ = 51156097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51157123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 263600 + ... + 263793.

It is an arithmetic number, because the mean of its divisors is an integer number (12921153).

Almost surely, 2^51157121 is an apocalyptic number.

It is an amenable number.

51157121 is a deficient number, since it is larger than the sum of its proper divisors (527491).

51157121 is an equidigital number, since it uses as much as digits as its factorization.

51157121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527490.

The product of its digits is 350, while the sum is 23.

The square root of 51157121 is about 7152.4206391962. The cubic root of 51157121 is about 371.2234180048.

The spelling of 51157121 in words is "fifty-one million, one hundred fifty-seven thousand, one hundred twenty-one".