646772900 has 54 divisors (see below), whose sum is σ = 1418163138. Its totient is φ = 256032000.

The previous prime is 646772897. The next prime is 646772941. The reversal of 646772900 is 9277646.

646772900 is digitally balanced in base 6, 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 3 ways, for example, as 202322176 + 444450724 = 14224^2 + 21082^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1612700 + ... + 1613100.

Almost surely, 2^646772900 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 646772900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (709081569).

646772900 is an abundant number, since it is smaller than the sum of its proper divisors (771390238).

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

646772900 is a wasteful number, since it uses less digits than its factorization.

646772900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 669 (or 535 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 41.

The square root of 646772900 is about 25431.7301810160. The cubic root of 646772900 is about 864.8031672599.

The spelling of 646772900 in words is "six hundred forty-six million, seven hundred seventy-two thousand, nine hundred".