51995213 has 4 divisors (see below), whose sum is σ = 53204448. Its totient is φ = 50785980.

The previous prime is 51995183. The next prime is 51995221. The reversal of 51995213 is 31259915.

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 51995213 - 2²⁴ = 35217997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51995243) 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, 604553 + ... + 604638.

It is an arithmetic number, because the mean of its divisors is an integer number (13301112).

Almost surely, 2^51995213 is an apocalyptic number.

It is an amenable number.

51995213 is a deficient number, since it is larger than the sum of its proper divisors (1209235).

51995213 is a wasteful number, since it uses less digits than its factorization.

51995213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1209234.

The product of its digits is 12150, while the sum is 35.

The square root of 51995213 is about 7210.7706245588. The cubic root of 51995213 is about 373.2396617848.

The spelling of 51995213 in words is "fifty-one million, nine hundred ninety-five thousand, two hundred thirteen".