649215684 has 36 divisors (see below), whose sum is σ = 1767310636. Its totient is φ = 199758528.

The previous prime is 649215659. The next prime is 649215691. The reversal of 649215684 is 486512946.

649215684 is a `hidden beast` number, since 6 + 492 + 156 + 8 + 4 = 666.

649215684 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 71774784 + 577440900 = 8472^2 + 24030^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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, 693139 + ... + 694074.

Almost surely, 2^649215684 is an apocalyptic number.

It is an amenable number.

649215684 is an abundant number, since it is smaller than the sum of its proper divisors (1118094952).

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

649215684 is a wasteful number, since it uses less digits than its factorization.

649215684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1387236 (or 1387231 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 649215684 is about 25479.7112228534. The cubic root of 649215684 is about 865.8905521925.

The spelling of 649215684 in words is "six hundred forty-nine million, two hundred fifteen thousand, six hundred eighty-four".