22445640 has 128 divisors (see below), whose sum is σ = 85536000. Its totient is φ = 5128704.

The previous prime is 22445639. The next prime is 22445641. The reversal of 22445640 is 4654422.

22445640 = 391² + 392² + ... + 502².

It is an interprime number because it is at equal distance from previous prime (22445639) and next prime (22445641).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22445641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6076 + ... + 9044.

It is an arithmetic number, because the mean of its divisors is an integer number (668250).

Almost surely, 2^22445640 is an apocalyptic number.

22445640 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 22445640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42768000).

22445640 is an abundant number, since it is smaller than the sum of its proper divisors (63090360).

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

22445640 is a wasteful number, since it uses less digits than its factorization.

22445640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2996 (or 2986 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 27.

The square root of 22445640 is about 4737.6829779967. The cubic root of 22445640 is about 282.0832710176.

The spelling of 22445640 in words is "twenty-two million, four hundred forty-five thousand, six hundred forty".