64081557 has 16 divisors (see below), whose sum is σ = 97999360. Its totient is φ = 41342400.

The previous prime is 64081541. The next prime is 64081579. The reversal of 64081557 is 75518046.

64081557 is a `hidden beast` number, since 640 + 8 + 1 + 5 + 5 + 7 = 666.

It is not a de Polignac number, because 64081557 - 2⁴ = 64081541 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64081957) 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, 37444 + ... + 39117.

It is an arithmetic number, because the mean of its divisors is an integer number (6124960).

Almost surely, 2^64081557 is an apocalyptic number.

It is an amenable number.

64081557 is a deficient number, since it is larger than the sum of its proper divisors (33917803).

64081557 is a wasteful number, since it uses less digits than its factorization.

64081557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76601 (or 76595 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 64081557 is about 8005.0956896217. The cubic root of 64081557 is about 400.1698382938.

The spelling of 64081557 in words is "sixty-four million, eighty-one thousand, five hundred fifty-seven".