649585440 has 192 divisors, whose sum is σ = 2598462720. Its totient is φ = 148469760.

The previous prime is 649585403. The next prime is 649585483. The reversal of 649585440 is 44585946.

649585440 is a `hidden beast` number, since 64 + 9 + 585 + 4 + 4 + 0 = 666.

649585440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×649585440² = 843922487719987200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19500 + ... + 40980.

It is an arithmetic number, because the mean of its divisors is an integer number (13533660).

Almost surely, 2^649585440 is an apocalyptic number.

649585440 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 649585440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1299231360).

649585440 is an abundant number, since it is smaller than the sum of its proper divisors (1948877280).

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

649585440 is a wasteful number, since it uses less digits than its factorization.

649585440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21512 (or 21498 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 45.

The square root of 649585440 is about 25486.9660807245. The cubic root of 649585440 is about 866.0549081844.

The spelling of 649585440 in words is "six hundred forty-nine million, five hundred eighty-five thousand, four hundred forty".