644374942253 has 16 divisors (see below), whose sum is σ = 738011022336. Its totient is φ = 551135767680.

The previous prime is 644374942249. The next prime is 644374942271. The reversal of 644374942253 is 352249473446.

644374942253 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 644374942253 - 2² = 644374942249 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 644374942195 and 644374942204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644374942213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6115625 + ... + 6220097.

It is an arithmetic number, because the mean of its divisors is an integer number (46125688896).

Almost surely, 2^644374942253 is an apocalyptic number.

It is an amenable number.

644374942253 is a deficient number, since it is larger than the sum of its proper divisors (93636080083).

644374942253 is a wasteful number, since it uses less digits than its factorization.

644374942253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106364.

The product of its digits is 17418240, while the sum is 53.

The spelling of 644374942253 in words is "six hundred forty-four billion, three hundred seventy-four million, nine hundred forty-two thousand, two hundred fifty-three".