51711813 has 24 divisors (see below), whose sum is σ = 78191360. Its totient is φ = 32892480.

The previous prime is 51711809. The next prime is 51711817. The reversal of 51711813 is 31811715.

It is an interprime number because it is at equal distance from previous prime (51711809) and next prime (51711817).

It is not a de Polignac number, because 51711813 - 2² = 51711809 is a prime.

It is a super-2 number, since 2×51711813² = 5348223207493938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51711817) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19098 + ... + 21636.

Almost surely, 2^51711813 is an apocalyptic number.

It is an amenable number.

51711813 is a deficient number, since it is larger than the sum of its proper divisors (26479547).

51711813 is a wasteful number, since it uses less digits than its factorization.

51711813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2649 (or 2646 counting only the distinct ones).

The product of its digits is 840, while the sum is 27.

The square root of 51711813 is about 7191.0926151733. The cubic root of 51711813 is about 372.5603115413.

The spelling of 51711813 in words is "fifty-one million, seven hundred eleven thousand, eight hundred thirteen".