51645783 has 16 divisors (see below), whose sum is σ = 81238016. Its totient is φ = 28559520.

The previous prime is 51645767. The next prime is 51645791. The reversal of 51645783 is 38754615.

It is not a de Polignac number, because 51645783 - 2⁴ = 51645767 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is the 7187-th Hogben number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51645703) by changing a digit.

It is a nontrivial repunit in base 7186.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39016 + ... + 40317.

It is an arithmetic number, because the mean of its divisors is an integer number (5077376).

Almost surely, 2^51645783 is an apocalyptic number.

51645783 is a deficient number, since it is larger than the sum of its proper divisors (29592233).

51645783 is a wasteful number, since it uses less digits than its factorization.

51645783 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79374.

The product of its digits is 100800, while the sum is 39.

The square root of 51645783 is about 7186.5000521812. The cubic root of 51645783 is about 372.4016718682.

The spelling of 51645783 in words is "fifty-one million, six hundred forty-five thousand, seven hundred eighty-three".