638826406772 has 24 divisors (see below), whose sum is σ = 1177878339456. Its totient is φ = 302559399648.

The previous prime is 638826406769. The next prime is 638826406781. The reversal of 638826406772 is 277604628836.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33698123 + ... + 33717074.

It is an arithmetic number, because the mean of its divisors is an integer number (49078264144).

Almost surely, 2^638826406772 is an apocalyptic number.

It is an amenable number.

638826406772 is a deficient number, since it is larger than the sum of its proper divisors (539051932684).

638826406772 is a wasteful number, since it uses less digits than its factorization.

638826406772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67415327 (or 67415325 counting only the distinct ones).

The product of its (nonzero) digits is 32514048, while the sum is 59.

The spelling of 638826406772 in words is "six hundred thirty-eight billion, eight hundred twenty-six million, four hundred six thousand, seven hundred seventy-two".