644525525446 has 16 divisors (see below), whose sum is σ = 1065120493968. Its totient is φ = 290065492000.

The previous prime is 644525525407. The next prime is 644525525461.

644525525446 is nontrivially palindromic in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 644525525393 and 644525525402.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 145030525 + ... + 145034968.

It is an arithmetic number, because the mean of its divisors is an integer number (66570030873).

Almost surely, 2^644525525446 is an apocalyptic number.

644525525446 is a deficient number, since it is larger than the sum of its proper divisors (420594968522).

644525525446 is a wasteful number, since it uses less digits than its factorization.

644525525446 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 290065607.

The product of its digits is 23040000, while the sum is 52.

The spelling of 644525525446 in words is "six hundred forty-four billion, five hundred twenty-five million, five hundred twenty-five thousand, four hundred forty-six".