637634997 has 40 divisors (see below), whose sum is σ = 1027693656. Its totient is φ = 392491008.

The previous prime is 637634983. The next prime is 637634999. The reversal of 637634997 is 799436736.

It can be written as a sum of positive squares in 4 ways, for example, as 199402641 + 438232356 = 14121^2 + 20934^2 .

It is not a de Polignac number, because 637634997 - 2⁴ = 637634981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (637634999) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 68613 + ... + 77349.

Almost surely, 2^637634997 is an apocalyptic number.

It is an amenable number.

637634997 is a deficient number, since it is larger than the sum of its proper divisors (390058659).

637634997 is a wasteful number, since it uses less digits than its factorization.

637634997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8819 (or 8810 counting only the distinct ones).

The product of its digits is 5143824, while the sum is 54.

The square root of 637634997 is about 25251.4355433508. The cubic root of 637634997 is about 860.7110565121.

The spelling of 637634997 in words is "six hundred thirty-seven million, six hundred thirty-four thousand, nine hundred ninety-seven".