22402640 has 60 divisors (see below), whose sum is σ = 56435004. Its totient is φ = 8266752.

The previous prime is 22402631. The next prime is 22402657. The reversal of 22402640 is 4620422.

It can be written as a sum of positive squares in 6 ways, for example, as 6210064 + 16192576 = 2492^2 + 4024^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

22402640 is a modest number, since divided by 2640 gives 2240 as remainder.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12692 + ... + 14348.

Almost surely, 2^22402640 is an apocalyptic number.

22402640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22402640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28217502).

22402640 is an abundant number, since it is smaller than the sum of its proper divisors (34032364).

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

22402640 is a wasteful number, since it uses less digits than its factorization.

22402640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1696 (or 1677 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 22402640 is about 4733.1427191666. The cubic root of 22402640 is about 281.9030231741.

The spelling of 22402640 in words is "twenty-two million, four hundred two thousand, six hundred forty".