639953205 has 16 divisors (see below), whose sum is σ = 1024964160. Its totient is φ = 340962048.

The previous prime is 639953203. The next prime is 639953207. The reversal of 639953205 is 502359936.

It is an interprime number because it is at equal distance from previous prime (639953203) and next prime (639953207).

It is not a de Polignac number, because 639953205 - 2¹ = 639953203 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639953201) 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, 6007 + ... + 36276.

It is an arithmetic number, because the mean of its divisors is an integer number (64060260).

Almost surely, 2^639953205 is an apocalyptic number.

It is an amenable number.

639953205 is a deficient number, since it is larger than the sum of its proper divisors (385010955).

639953205 is a wasteful number, since it uses less digits than its factorization.

639953205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43300.

The product of its (nonzero) digits is 218700, while the sum is 42.

The square root of 639953205 is about 25297.2963970461. The cubic root of 639953205 is about 861.7528720068.

The spelling of 639953205 in words is "six hundred thirty-nine million, nine hundred fifty-three thousand, two hundred five".