646987392 has 256 divisors, whose sum is σ = 2056320000. Its totient is φ = 199646208.

The previous prime is 646987387. The next prime is 646987409. The reversal of 646987392 is 293789646.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3874093 + ... + 3874259.

It is an arithmetic number, because the mean of its divisors is an integer number (8032500).

Almost surely, 2^646987392 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646987392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1028160000).

646987392 is an abundant number, since it is smaller than the sum of its proper divisors (1409332608).

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

646987392 is a wasteful number, since it uses less digits than its factorization.

646987392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268 (or 250 counting only the distinct ones).

The product of its digits is 3919104, while the sum is 54.

The square root of 646987392 is about 25435.9468469330. The cubic root of 646987392 is about 864.8987561235.

The spelling of 646987392 in words is "six hundred forty-six million, nine hundred eighty-seven thousand, three hundred ninety-two".