639397276394 has 8 divisors (see below), whose sum is σ = 961167397440. Its totient is φ = 319008143916.

The previous prime is 639397276391. The next prime is 639397276433. The reversal of 639397276394 is 493672793936.

639397276394 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×639397276394³ (a number of 36 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (639397276391) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 345245984 + ... + 345247835.

It is an arithmetic number, because the mean of its divisors is an integer number (120145924680).

Almost surely, 2^639397276394 is an apocalyptic number.

639397276394 is a deficient number, since it is larger than the sum of its proper divisors (321770121046).

639397276394 is a wasteful number, since it uses less digits than its factorization.

639397276394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690494284.

The product of its digits is 277766496, while the sum is 68.

The spelling of 639397276394 in words is "six hundred thirty-nine billion, three hundred ninety-seven million, two hundred seventy-six thousand, three hundred ninety-four".