634264665621 has 16 divisors (see below), whose sum is σ = 895469468544. Its totient is φ = 397953542144.

The previous prime is 634264665581. The next prime is 634264665631. The reversal of 634264665621 is 126566462436.

It is a cyclic number.

It is not a de Polignac number, because 634264665621 - 2⁶ = 634264665557 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634264665631) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1054405 + ... + 1542821.

It is an arithmetic number, because the mean of its divisors is an integer number (55966841784).

Almost surely, 2^634264665621 is an apocalyptic number.

It is an amenable number.

634264665621 is a deficient number, since it is larger than the sum of its proper divisors (261204802923).

634264665621 is a wasteful number, since it uses less digits than its factorization.

634264665621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513900.

The product of its digits is 7464960, while the sum is 51.

The spelling of 634264665621 in words is "six hundred thirty-four billion, two hundred sixty-four million, six hundred sixty-five thousand, six hundred twenty-one".