51384631 has 4 divisors (see below), whose sum is σ = 52227064. Its totient is φ = 50542200.

The previous prime is 51384611. The next prime is 51384637. The reversal of 51384631 is 13648315.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51384631 - 2⁹ = 51384119 is a prime.

It is a super-2 number, since 2×51384631² = 5280760606012322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51384593 and 51384602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51384637) 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, 421125 + ... + 421246.

It is an arithmetic number, because the mean of its divisors is an integer number (13056766).

Almost surely, 2^51384631 is an apocalyptic number.

51384631 is a deficient number, since it is larger than the sum of its proper divisors (842433).

51384631 is an equidigital number, since it uses as much as digits as its factorization.

51384631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 842432.

The product of its digits is 8640, while the sum is 31.

The square root of 51384631 is about 7168.3074013326. The cubic root of 51384631 is about 371.7729156130.

The spelling of 51384631 in words is "fifty-one million, three hundred eighty-four thousand, six hundred thirty-one".