640280040 has 32 divisors (see below), whose sum is σ = 1920840480. Its totient is φ = 170741312.

The previous prime is 640280029. The next prime is 640280057. The reversal of 640280040 is 40082046.

640280040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2667714 + ... + 2667953.

It is an arithmetic number, because the mean of its divisors is an integer number (60026265).

Almost surely, 2^640280040 is an apocalyptic number.

640280040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

640280040 is an abundant number, since it is smaller than the sum of its proper divisors (1280560440).

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

640280040 is a wasteful number, since it uses less digits than its factorization.

640280040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5335681 (or 5335677 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 640280040 is about 25303.7554525015. The cubic root of 640280040 is about 861.8995509949.

The spelling of 640280040 in words is "six hundred forty million, two hundred eighty thousand, forty".