64856537 has 8 divisors (see below), whose sum is σ = 65427912. Its totient is φ = 64288000.

The previous prime is 64856521. The next prime is 64856593. The reversal of 64856537 is 73565846.

It can be written as a sum of positive squares in 4 ways, for example, as 42237001 + 22619536 = 6499^2 + 4756^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 64856537 - 2⁴ = 64856521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64856437) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78587 + ... + 79407.

It is an arithmetic number, because the mean of its divisors is an integer number (8178489).

Almost surely, 2^64856537 is an apocalyptic number.

It is an amenable number.

64856537 is a deficient number, since it is larger than the sum of its proper divisors (571375).

64856537 is a wasteful number, since it uses less digits than its factorization.

64856537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1419.

The product of its digits is 604800, while the sum is 44.

The square root of 64856537 is about 8053.3556360066. The cubic root of 64856537 is about 401.7765500766.

The spelling of 64856537 in words is "sixty-four million, eight hundred fifty-six thousand, five hundred thirty-seven".