649008240 has 80 divisors (see below), whose sum is σ = 2025540000. Its totient is φ = 171897856.

The previous prime is 649008221. The next prime is 649008277. The reversal of 649008240 is 42800946.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26686 + ... + 44834.

It is an arithmetic number, because the mean of its divisors is an integer number (25319250).

Almost surely, 2^649008240 is an apocalyptic number.

649008240 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 649008240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1012770000).

649008240 is an abundant number, since it is smaller than the sum of its proper divisors (1376531760).

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

649008240 is a wasteful number, since it uses less digits than its factorization.

649008240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18314 (or 18308 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 649008240 is about 25475.6401293471. The cubic root of 649008240 is about 865.7983163151.

The spelling of 649008240 in words is "six hundred forty-nine million, eight thousand, two hundred forty".