637428123 has 14 divisors (see below), whose sum is σ = 955706084. Its totient is φ = 424951596.

The previous prime is 637428097. The next prime is 637428133. The reversal of 637428123 is 321824736.

It is a happy number.

637428123 is a `hidden beast` number, since 6 + 374 + 281 + 2 + 3 = 666.

It is not a de Polignac number, because 637428123 - 2¹⁸ = 637165979 is a prime.

It is a super-2 number, since 2×637428123² = 812629223982606258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (637428133) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 436465 + ... + 437922.

Almost surely, 2^637428123 is an apocalyptic number.

637428123 is a deficient number, since it is larger than the sum of its proper divisors (318277961).

637428123 is an frugal number, since it uses more digits than its factorization.

637428123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 874405 (or 874390 counting only the distinct ones).

The product of its digits is 48384, while the sum is 36.

The square root of 637428123 is about 25247.3389290832. The cubic root of 637428123 is about 860.6179635462.

The spelling of 637428123 in words is "six hundred thirty-seven million, four hundred twenty-eight thousand, one hundred twenty-three".