51204137 has 4 divisors (see below), whose sum is σ = 51530436. Its totient is φ = 50877840.

The previous prime is 51204133. The next prime is 51204143. The reversal of 51204137 is 73140215.

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 38700841 + 12503296 = 6221^2 + 3536^2 .

It is a cyclic number.

It is not a de Polignac number, because 51204137 - 2² = 51204133 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51204133) 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, 162914 + ... + 163227.

It is an arithmetic number, because the mean of its divisors is an integer number (12882609).

Almost surely, 2^51204137 is an apocalyptic number.

It is an amenable number.

51204137 is a deficient number, since it is larger than the sum of its proper divisors (326299).

51204137 is a wasteful number, since it uses less digits than its factorization.

51204137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326298.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 51204137 is about 7155.7066038233. The cubic root of 51204137 is about 371.3371075931.

The spelling of 51204137 in words is "fifty-one million, two hundred four thousand, one hundred thirty-seven".