639120777 has 8 divisors (see below), whose sum is σ = 852707040. Its totient is φ = 425807520.

The previous prime is 639120773. The next prime is 639120787. The reversal of 639120777 is 777021936.

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

It is not a de Polignac number, because 639120777 - 2² = 639120773 is a prime.

It is not an unprimeable number, because it can be changed into a prime (639120773) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62724 + ... + 72197.

It is an arithmetic number, because the mean of its divisors is an integer number (106588380).

Almost surely, 2^639120777 is an apocalyptic number.

It is an amenable number.

639120777 is a deficient number, since it is larger than the sum of its proper divisors (213586263).

639120777 is a wasteful number, since it uses less digits than its factorization.

639120777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136503.

The product of its (nonzero) digits is 111132, while the sum is 42.

The square root of 639120777 is about 25280.8381387960. The cubic root of 639120777 is about 861.3790642178.

The spelling of 639120777 in words is "six hundred thirty-nine million, one hundred twenty thousand, seven hundred seventy-seven".