637920253 has 4 divisors (see below), whose sum is σ = 637972348. Its totient is φ = 637868160.

The previous prime is 637920251. The next prime is 637920259. The reversal of 637920253 is 352029736.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 608954329 + 28965924 = 24677^2 + 5382^2 .

It is a cyclic number.

It is not a de Polignac number, because 637920253 - 2¹ = 637920251 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 (637920251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3475 + ... + 35887.

It is an arithmetic number, because the mean of its divisors is an integer number (159493087).

Almost surely, 2^637920253 is an apocalyptic number.

It is an amenable number.

637920253 is a deficient number, since it is larger than the sum of its proper divisors (52095).

637920253 is a wasteful number, since it uses less digits than its factorization.

637920253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52094.

The product of its (nonzero) digits is 68040, while the sum is 37.

The square root of 637920253 is about 25257.0832243155. The cubic root of 637920253 is about 860.8393882329.

Adding to 637920253 its reverse (352029736), we get a palindrome (989949989).

The spelling of 637920253 in words is "six hundred thirty-seven million, nine hundred twenty thousand, two hundred fifty-three".