646986900 has 144 divisors (see below), whose sum is σ = 2180110464. Its totient is φ = 145067520.

The previous prime is 646986889. The next prime is 646986931. The reversal of 646986900 is 9689646.

It is a super-2 number, since 2×646986900² = 837184097543220000, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 646986900.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 108394 + ... + 114206.

It is an arithmetic number, because the mean of its divisors is an integer number (15139656).

Almost surely, 2^646986900 is an apocalyptic number.

646986900 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646986900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1090055232).

646986900 is an abundant number, since it is smaller than the sum of its proper divisors (1533123564).

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

646986900 is a wasteful number, since it uses less digits than its factorization.

646986900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5890 (or 5883 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 48.

The square root of 646986900 is about 25435.9371755790. The cubic root of 646986900 is about 864.8985368867.

The spelling of 646986900 in words is "six hundred forty-six million, nine hundred eighty-six thousand, nine hundred".