644752638098 has 8 divisors (see below), whose sum is σ = 970179838092. Its totient is φ = 321359358736.

The previous prime is 644752638083. The next prime is 644752638227. The reversal of 644752638098 is 890836257446.

It can be written as a sum of positive squares in 2 ways, for example, as 644659650649 + 92987449 = 802907^2 + 9643^2 .

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

It is a super-2 number, since 2×644752638098² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 644752638098.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 508479365 + ... + 508480632.

Almost surely, 2^644752638098 is an apocalyptic number.

644752638098 is a deficient number, since it is larger than the sum of its proper divisors (325427199994).

644752638098 is a wasteful number, since it uses less digits than its factorization.

644752638098 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1016960316.

The product of its (nonzero) digits is 69672960, while the sum is 62.

The spelling of 644752638098 in words is "six hundred forty-four billion, seven hundred fifty-two million, six hundred thirty-eight thousand, ninety-eight".