640072 has 16 divisors (see below), whose sum is σ = 1263600. Its totient is φ = 303120.

The previous prime is 640069. The next prime is 640099. The reversal of 640072 is 270046.

It is a Harshad number since it is a multiple of its sum of digits (19).

640072 is a modest number, since divided by 72 gives 64 as remainder.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1954 + ... + 2257.

It is an arithmetic number, because the mean of its divisors is an integer number (78975).

2⁶⁴⁰⁰⁷² is an apocalyptic number.

It is an amenable number.

640072 is a deficient number, since it is larger than the sum of its proper divisors (623528).

640072 is a wasteful number, since it uses less digits than its factorization.

640072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4236 (or 4232 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 640072 is about 800.0449987344. The cubic root of 640072 is about 86.1806191321.

It can be divided in two parts, 64007 and 2, that added together give a square (64009 = 253²).

The spelling of 640072 in words is "six hundred forty thousand, seventy-two".