639698097 has 8 divisors (see below), whose sum is σ = 853414720. Its totient is φ = 426223440.

The previous prime is 639698047. The next prime is 639698123. The reversal of 639698097 is 790896936.

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

It is not a de Polignac number, because 639698097 - 2⁸ = 639697841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (639698047) 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, 54229 + ... + 64962.

It is an arithmetic number, because the mean of its divisors is an integer number (106676840).

Almost surely, 2^639698097 is an apocalyptic number.

It is an amenable number.

639698097 is a deficient number, since it is larger than the sum of its proper divisors (213716623).

639698097 is a wasteful number, since it uses less digits than its factorization.

639698097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120983.

The product of its (nonzero) digits is 4408992, while the sum is 57.

The square root of 639698097 is about 25292.2536955488. The cubic root of 639698097 is about 861.6383483883.

The spelling of 639698097 in words is "six hundred thirty-nine million, six hundred ninety-eight thousand, ninety-seven".