649978400 has 36 divisors (see below), whose sum is σ = 1586761722. Its totient is φ = 259991040.

The previous prime is 649978393. The next prime is 649978403. The reversal of 649978400 is 4879946.

It can be written as a sum of positive squares in 3 ways, for example, as 544382224 + 105596176 = 23332^2 + 10276^2 .

It is not an unprimeable number, because it can be changed into a prime (649978403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 405437 + ... + 407036.

Almost surely, 2^649978400 is an apocalyptic number.

It is an amenable number.

649978400 is an abundant number, since it is smaller than the sum of its proper divisors (936783322).

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

649978400 is a wasteful number, since it uses less digits than its factorization.

649978400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812493 (or 812480 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 47.

The square root of 649978400 is about 25494.6739535927. The cubic root of 649978400 is about 866.2295099707.

The spelling of 649978400 in words is "six hundred forty-nine million, nine hundred seventy-eight thousand, four hundred".