644610423626131 has 16 divisors (see below), whose sum is σ = 676419956352000. Its totient is φ = 613492616311200.

The previous prime is 644610423626129. The next prime is 644610423626227. The reversal of 644610423626131 is 131626324016446.

It is a cyclic number.

It is not a de Polignac number, because 644610423626131 - 2¹ = 644610423626129 is a prime.

It is a super-3 number, since 3×644610423626131³ (a number of 45 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (644610423626531) 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, 15147121 + ... + 38969938.

It is an arithmetic number, because the mean of its divisors is an integer number (42276247272000).

Almost surely, 2^{644610423626131} is an apocalyptic number.

644610423626131 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

644610423626131 is a deficient number, since it is larger than the sum of its proper divisors (31809532725869).

644610423626131 is a wasteful number, since it uses less digits than its factorization.

644610423626131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54123450.

The product of its (nonzero) digits is 2985984, while the sum is 49.

The spelling of 644610423626131 in words is "six hundred forty-four trillion, six hundred ten billion, four hundred twenty-three million, six hundred twenty-six thousand, one hundred thirty-one".