51640715 has 16 divisors (see below), whose sum is σ = 72737472. Its totient is φ = 34452864.

The previous prime is 51640697. The next prime is 51640717. The reversal of 51640715 is 51704615.

It is a cyclic number.

It is not a de Polignac number, because 51640715 - 2¹⁶ = 51575179 is a prime.

It is a super-2 number, since 2×51640715² = 5333526891422450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51640717) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18644 + ... + 21233.

It is an arithmetic number, because the mean of its divisors is an integer number (4546092).

Almost surely, 2^51640715 is an apocalyptic number.

51640715 is a deficient number, since it is larger than the sum of its proper divisors (21096757).

51640715 is a wasteful number, since it uses less digits than its factorization.

51640715 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39926.

The product of its (nonzero) digits is 4200, while the sum is 29.

The square root of 51640715 is about 7186.1474379531. The cubic root of 51640715 is about 372.3894902127.

The spelling of 51640715 in words is "fifty-one million, six hundred forty thousand, seven hundred fifteen".