640710980 has 96 divisors (see below), whose sum is σ = 1665328896. Its totient is φ = 201632256.

The previous prime is 640710929. The next prime is 640710997. The reversal of 640710980 is 89017046.

It is a super-3 number, since 3×640710980³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 640710980.

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, 357647 + ... + 359433.

It is an arithmetic number, because the mean of its divisors is an integer number (17347176).

Almost surely, 2^640710980 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 640710980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (832664448).

640710980 is an abundant number, since it is smaller than the sum of its proper divisors (1024617916).

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

640710980 is a wasteful number, since it uses less digits than its factorization.

640710980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2013 (or 2011 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 640710980 is about 25312.2693569739. The cubic root of 640710980 is about 862.0928745777.

The spelling of 640710980 in words is "six hundred forty million, seven hundred ten thousand, nine hundred eighty".