634659857 has 4 divisors (see below), whose sum is σ = 683479860. Its totient is φ = 585839856.

The previous prime is 634659757. The next prime is 634659859. The reversal of 634659857 is 758956436.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 393665281 + 240994576 = 19841^2 + 15524^2 .

It is a cyclic number.

It is not a de Polignac number, because 634659857 - 2⁸ = 634659601 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 634659799 and 634659808.

It is not an unprimeable number, because it can be changed into a prime (634659859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24409982 + ... + 24410007.

It is an arithmetic number, because the mean of its divisors is an integer number (170869965).

Almost surely, 2^634659857 is an apocalyptic number.

It is an amenable number.

634659857 is a deficient number, since it is larger than the sum of its proper divisors (48820003).

634659857 is a wasteful number, since it uses less digits than its factorization.

634659857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48820002.

The product of its digits is 5443200, while the sum is 53.

The square root of 634659857 is about 25192.4563510587. The cubic root of 634659857 is about 859.3703056793.

The spelling of 634659857 in words is "six hundred thirty-four million, six hundred fifty-nine thousand, eight hundred fifty-seven".