640161357 has 16 divisors (see below), whose sum is σ = 980152320. Its totient is φ = 367556400.

The previous prime is 640161337. The next prime is 640161371. The reversal of 640161357 is 753161046.

It is not a de Polignac number, because 640161357 - 2⁶ = 640161293 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640161337) 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, 509869 + ... + 511122.

It is an arithmetic number, because the mean of its divisors is an integer number (61259520).

Almost surely, 2^640161357 is an apocalyptic number.

It is an amenable number.

640161357 is a deficient number, since it is larger than the sum of its proper divisors (339990963).

640161357 is a wasteful number, since it uses less digits than its factorization.

640161357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1021024.

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 640161357 is about 25301.4101780909. The cubic root of 640161357 is about 861.8462934934.

The spelling of 640161357 in words is "six hundred forty million, one hundred sixty-one thousand, three hundred fifty-seven".