640752201 has 10 divisors (see below), whose sum is σ = 957173162. Its totient is φ = 427168080.

The previous prime is 640752197. The next prime is 640752227. The reversal of 640752201 is 102257046.

640752201 is a `hidden beast` number, since 6 + 407 + 52 + 201 = 666.

It can be written as a sum of positive squares in only one way, i.e., 496175625 + 144576576 = 22275^2 + 12024^2 .

It is not a de Polignac number, because 640752201 - 2² = 640752197 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640752241) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3955180 + ... + 3955341.

Almost surely, 2^640752201 is an apocalyptic number.

It is an amenable number.

640752201 is a deficient number, since it is larger than the sum of its proper divisors (316420961).

640752201 is an equidigital number, since it uses as much as digits as its factorization.

640752201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7910533 (or 7910524 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 640752201 is about 25313.0835932725. The cubic root of 640752201 is about 862.1113621483. Note that the first 3 decimals are identical.

The spelling of 640752201 in words is "six hundred forty million, seven hundred fifty-two thousand, two hundred one".