51640823 has 12 divisors (see below), whose sum is σ = 57728448. Its totient is φ = 46126080.

The previous prime is 51640811. The next prime is 51640829. The reversal of 51640823 is 32804615.

It is not a de Polignac number, because 51640823 - 2¹² = 51636727 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51640829) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 311 + ... + 10167.

It is an arithmetic number, because the mean of its divisors is an integer number (4810704).

Almost surely, 2^51640823 is an apocalyptic number.

51640823 is a deficient number, since it is larger than the sum of its proper divisors (6087625).

51640823 is a wasteful number, since it uses less digits than its factorization.

51640823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9914 (or 9901 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 51640823 is about 7186.1549524067. The cubic root of 51640823 is about 372.3897498143.

The spelling of 51640823 in words is "fifty-one million, six hundred forty thousand, eight hundred twenty-three".