646738144 has 24 divisors (see below), whose sum is σ = 1371210120. Its totient is φ = 298494336.

The previous prime is 646738129. The next prime is 646738177. The reversal of 646738144 is 441837646.

It is a self number, because there is not a number n which added to its sum of digits gives 646738144.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 776914 + ... + 777745.

It is an arithmetic number, because the mean of its divisors is an integer number (57133755).

Almost surely, 2^646738144 is an apocalyptic number.

It is an amenable number.

646738144 is an abundant number, since it is smaller than the sum of its proper divisors (724471976).

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

646738144 is a wasteful number, since it uses less digits than its factorization.

646738144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1554682 (or 1554674 counting only the distinct ones).

The product of its digits is 387072, while the sum is 43.

The square root of 646738144 is about 25431.0468522238. The cubic root of 646738144 is about 864.7876761773.

The spelling of 646738144 in words is "six hundred forty-six million, seven hundred thirty-eight thousand, one hundred forty-four".