638648714026 has 8 divisors (see below), whose sum is σ = 966761815140. Its totient is φ = 316394775648.

The previous prime is 638648713951. The next prime is 638648714029. The reversal of 638648714026 is 620417846836.

It is a happy number.

It is a Cunningham number, because it is equal to 799155²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 638648714025 + 1 = 799155^2 + 1^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (638648714029) 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, 1464790411 + ... + 1464790846.

Almost surely, 2^638648714026 is an apocalyptic number.

638648714026 is a deficient number, since it is larger than the sum of its proper divisors (328113101114).

638648714026 is a wasteful number, since it uses less digits than its factorization.

638648714026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2929581368.

The product of its (nonzero) digits is 9289728, while the sum is 55.

The spelling of 638648714026 in words is "six hundred thirty-eight billion, six hundred forty-eight million, seven hundred fourteen thousand, twenty-six".