646974100 has 72 divisors (see below), whose sum is σ = 1491654528. Its totient is φ = 242726400.

The previous prime is 646974091. The next prime is 646974101. The reversal of 646974100 is 1479646.

It is a self number, because there is not a number n which added to its sum of digits gives 646974100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646974101) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 732259 + ... + 733141.

It is an arithmetic number, because the mean of its divisors is an integer number (20717424).

Almost surely, 2^646974100 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 646974100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (745827264).

646974100 is an abundant number, since it is smaller than the sum of its proper divisors (844680428).

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

646974100 is a wasteful number, since it uses less digits than its factorization.

646974100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1345 (or 1338 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 646974100 is about 25435.6855618244. The cubic root of 646974100 is about 864.8928331265.

The spelling of 646974100 in words is "six hundred forty-six million, nine hundred seventy-four thousand, one hundred".