646138777144 has 48 divisors (see below), whose sum is σ = 1410191630280. Its totient is φ = 276742952640.

The previous prime is 646138777139. The next prime is 646138777157. The reversal of 646138777144 is 441777831646.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 109959 + ... + 1142089.

Almost surely, 2^646138777144 is an apocalyptic number.

It is an amenable number.

646138777144 is an abundant number, since it is smaller than the sum of its proper divisors (764052853136).

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

646138777144 is a wasteful number, since it uses less digits than its factorization.

646138777144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1033748 (or 1033737 counting only the distinct ones).

The product of its digits is 18966528, while the sum is 58.

The spelling of 646138777144 in words is "six hundred forty-six billion, one hundred thirty-eight million, seven hundred seventy-seven thousand, one hundred forty-four".