638491479654 has 16 divisors (see below), whose sum is σ = 1459409096448. Its totient is φ = 182426137032.

The previous prime is 638491479643. The next prime is 638491479739. The reversal of 638491479654 is 456974194836.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7601089002 + ... + 7601089085.

It is an arithmetic number, because the mean of its divisors is an integer number (91213068528).

Almost surely, 2^638491479654 is an apocalyptic number.

638491479654 is an abundant number, since it is smaller than the sum of its proper divisors (820917616794).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

638491479654 is a wasteful number, since it uses less digits than its factorization.

638491479654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15202178099.

The product of its digits is 156764160, while the sum is 66.

The spelling of 638491479654 in words is "six hundred thirty-eight billion, four hundred ninety-one million, four hundred seventy-nine thousand, six hundred fifty-four".