51213145 has 16 divisors (see below), whose sum is σ = 62449920. Its totient is φ = 40313664.

The previous prime is 51213139. The next prime is 51213179. The reversal of 51213145 is 54131215.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 51213145 - 2³ = 51213137 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 142476 + ... + 142834.

It is an arithmetic number, because the mean of its divisors is an integer number (3903120).

Almost surely, 2^51213145 is an apocalyptic number.

It is an amenable number.

51213145 is a deficient number, since it is larger than the sum of its proper divisors (11236775).

51213145 is a wasteful number, since it uses less digits than its factorization.

51213145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 744.

The product of its digits is 600, while the sum is 22.

The square root of 51213145 is about 7156.3360038500. The cubic root of 51213145 is about 371.3588819309.

The spelling of 51213145 in words is "fifty-one million, two hundred thirteen thousand, one hundred forty-five".