638081807 has 16 divisors (see below), whose sum is σ = 739864320. Its totient is φ = 544190400.

The previous prime is 638081789. The next prime is 638081813. The reversal of 638081807 is 708180836.

It is not a de Polignac number, because 638081807 - 2²⁴ = 621304591 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 (638081827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6707 + ... + 36347.

It is an arithmetic number, because the mean of its divisors is an integer number (46241520).

Almost surely, 2^638081807 is an apocalyptic number.

638081807 is a deficient number, since it is larger than the sum of its proper divisors (101782513).

638081807 is a wasteful number, since it uses less digits than its factorization.

638081807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29774.

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 638081807 is about 25260.2812137949. The cubic root of 638081807 is about 860.9120516040.

The spelling of 638081807 in words is "six hundred thirty-eight million, eighty-one thousand, eight hundred seven".