22651440 has 160 divisors (see below), whose sum is σ = 81661440. Its totient is φ = 5087232.

The previous prime is 22651423. The next prime is 22651441. The reversal of 22651440 is 4415622.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 22651440.

It is not an unprimeable number, because it can be changed into a prime (22651441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 162891 + ... + 163029.

It is an arithmetic number, because the mean of its divisors is an integer number (510384).

Almost surely, 2^22651440 is an apocalyptic number.

22651440 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 22651440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40830720).

22651440 is an abundant number, since it is smaller than the sum of its proper divisors (59010000).

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

22651440 is a wasteful number, since it uses less digits than its factorization.

22651440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 259 (or 253 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 22651440 is about 4759.3528971910. The cubic root of 22651440 is about 282.9427729141.

The spelling of 22651440 in words is "twenty-two million, six hundred fifty-one thousand, four hundred forty".