639351461 has 6 divisors (see below), whose sum is σ = 743735430. Its totient is φ = 548015496.

The previous prime is 639351457. The next prime is 639351469. The reversal of 639351461 is 164153936.

It can be written as a sum of positive squares in only one way, i.e., 409252900 + 230098561 = 20230^2 + 15169^2 .

It is not a de Polignac number, because 639351461 - 2² = 639351457 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639351469) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6523946 + ... + 6524043.

It is an arithmetic number, because the mean of its divisors is an integer number (123955905).

Almost surely, 2^639351461 is an apocalyptic number.

It is an amenable number.

639351461 is a deficient number, since it is larger than the sum of its proper divisors (104383969).

639351461 is a wasteful number, since it uses less digits than its factorization.

639351461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13048003 (or 13047996 counting only the distinct ones).

The product of its digits is 58320, while the sum is 38.

The square root of 639351461 is about 25285.4001550302. The cubic root of 639351461 is about 861.4826870243.

The spelling of 639351461 in words is "six hundred thirty-nine million, three hundred fifty-one thousand, four hundred sixty-one".