644511954 has 16 divisors (see below), whose sum is σ = 1323862848. Its totient is φ = 209030832.

The previous prime is 644511913. The next prime is 644511971. The reversal of 644511954 is 459115446.

644511954 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1451382 + ... + 1451825.

It is an arithmetic number, because the mean of its divisors is an integer number (82741428).

Almost surely, 2^644511954 is an apocalyptic number.

644511954 is an abundant number, since it is smaller than the sum of its proper divisors (679350894).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

644511954 is a wasteful number, since it uses less digits than its factorization.

644511954 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2903249.

The product of its digits is 86400, while the sum is 39.

The square root of 644511954 is about 25387.2399838974. The cubic root of 644511954 is about 863.7942834778.

The spelling of 644511954 in words is "six hundred forty-four million, five hundred eleven thousand, nine hundred fifty-four".