22878640 has 20 divisors (see below), whose sum is σ = 53193024. Its totient is φ = 9151424.

The previous prime is 22878619. The next prime is 22878643. The reversal of 22878640 is 4687822.

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 22878640.

It is not an unprimeable number, because it can be changed into a prime (22878643) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 142912 + ... + 143071.

Almost surely, 2^22878640 is an apocalyptic number.

22878640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22878640 is an abundant number, since it is smaller than the sum of its proper divisors (30314384).

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

22878640 is a wasteful number, since it uses less digits than its factorization.

22878640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285996 (or 285990 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 37.

The square root of 22878640 is about 4783.1621339863. The cubic root of 22878640 is about 283.8856247764.

It can be divided in two parts, 228786 and 40, that added together give a triangular number (228826 = T₆₇₆).

The spelling of 22878640 in words is "twenty-two million, eight hundred seventy-eight thousand, six hundred forty".