646278084 has 81 divisors (see below), whose sum is σ = 1731920463. Its totient is φ = 203172624.

The previous prime is 646278071. The next prime is 646278109. The reversal of 646278084 is 480872646.

The square root of 646278084 is 25422.

It is a perfect power (a square), and thus also a powerful number.

It is a super-2 number, since 2×646278084² = 835350723717422112, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2897997 + ... + 2898219.

Almost surely, 2^646278084 is an apocalyptic number.

646278084 is the 25422-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646278084

646278084 is an abundant number, since it is smaller than the sum of its proper divisors (1085642379).

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

646278084 is a wasteful number, since it uses less digits than its factorization.

646278084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 494 (or 247 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 45.

The cubic root of 646278084 is about 864.5825707068.

The spelling of 646278084 in words is "six hundred forty-six million, two hundred seventy-eight thousand, eighty-four".