72078640 has 40 divisors (see below), whose sum is σ = 177444000. Its totient is φ = 27134976.

The previous prime is 72078613. The next prime is 72078649. The reversal of 72078640 is 4687027.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a junction number, because it is equal to n+sod(n) for n = 72078596 and 72078605.

It is not an unprimeable number, because it can be changed into a prime (72078649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25140 + ... + 27859.

It is an arithmetic number, because the mean of its divisors is an integer number (4436100).

Almost surely, 2^72078640 is an apocalyptic number.

It is an amenable number.

72078640 is an abundant number, since it is smaller than the sum of its proper divisors (105365360).

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

72078640 is a wasteful number, since it uses less digits than its factorization.

72078640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53029 (or 53023 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 34.

The square root of 72078640 is about 8489.9140160546. The cubic root of 72078640 is about 416.1681704192.

The spelling of 72078640 in words is "seventy-two million, seventy-eight thousand, six hundred forty".