51640858 has 4 divisors (see below), whose sum is σ = 77461290. Its totient is φ = 25820428.

The previous prime is 51640847. The next prime is 51640859. The reversal of 51640858 is 85804615.

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

It can be written as a sum of positive squares in only one way, i.e., 51595489 + 45369 = 7183^2 + 213^2 .

It is not an unprimeable number, because it can be changed into a prime (51640859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12910213 + ... + 12910216.

Almost surely, 2^51640858 is an apocalyptic number.

51640858 is a deficient number, since it is larger than the sum of its proper divisors (25820432).

51640858 is a wasteful number, since it uses less digits than its factorization.

51640858 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25820431.

The product of its (nonzero) digits is 38400, while the sum is 37.

The square root of 51640858 is about 7186.1573876447. The cubic root of 51640858 is about 372.3898339444.

The spelling of 51640858 in words is "fifty-one million, six hundred forty thousand, eight hundred fifty-eight".