764408638 has 32 divisors (see below), whose sum is σ = 1389484800. Its totient is φ = 307891584.

The previous prime is 764408573. The next prime is 764408639. The reversal of 764408638 is 836804467.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (764408639) 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, 202573 + ... + 206311.

It is an arithmetic number, because the mean of its divisors is an integer number (43421400).

Almost surely, 2^764408638 is an apocalyptic number.

764408638 is a deficient number, since it is larger than the sum of its proper divisors (625076162).

764408638 is a wasteful number, since it uses less digits than its factorization.

764408638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4624.

The product of its (nonzero) digits is 774144, while the sum is 46.

The square root of 764408638 is about 27647.9409359902. The cubic root of 764408638 is about 914.3417037350.

It can be divided in two parts, 76440 and 8638, that added together give a triangular number (85078 = T₄₁₂).

The spelling of 764408638 in words is "seven hundred sixty-four million, four hundred eight thousand, six hundred thirty-eight".