634985651 has 4 divisors (see below), whose sum is σ = 648496032. Its totient is φ = 621475272.

The previous prime is 634985639. The next prime is 634985669. The reversal of 634985651 is 156589436.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 634985651 - 2¹⁴ = 634969267 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (47), and also a Moran number because the ratio is a prime number: 13510333 = 634985651 / (6 + 3 + 4 + 9 + 8 + 5 + 6 + 5 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 634985596 and 634985605.

It is not an unprimeable number, because it can be changed into a prime (634985621) 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, 6755120 + ... + 6755213.

It is an arithmetic number, because the mean of its divisors is an integer number (162124008).

Almost surely, 2^634985651 is an apocalyptic number.

634985651 is a deficient number, since it is larger than the sum of its proper divisors (13510381).

634985651 is a wasteful number, since it uses less digits than its factorization.

634985651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13510380.

The product of its digits is 777600, while the sum is 47.

The square root of 634985651 is about 25198.9216237521. The cubic root of 634985651 is about 859.5173292081.

The spelling of 634985651 in words is "six hundred thirty-four million, nine hundred eighty-five thousand, six hundred fifty-one".