649642280 has 128 divisors (see below), whose sum is σ = 1733529600. Its totient is φ = 214486272.

The previous prime is 649642277. The next prime is 649642309. The reversal of 649642280 is 82246946.

649642280 = T₂₀₉ + T₂₁₀ + ... + T₁₅₇₄.

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, 950819 + ... + 951501.

It is an arithmetic number, because the mean of its divisors is an integer number (13543200).

Almost surely, 2^649642280 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 649642280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (866764800).

649642280 is an abundant number, since it is smaller than the sum of its proper divisors (1083887320).

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

649642280 is a wasteful number, since it uses less digits than its factorization.

649642280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823 (or 819 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 41.

The square root of 649642280 is about 25488.0811360918. The cubic root of 649642280 is about 866.0801679487.

The spelling of 649642280 in words is "six hundred forty-nine million, six hundred forty-two thousand, two hundred eighty".