22515440 has 40 divisors (see below), whose sum is σ = 52550208. Its totient is φ = 8971520.

The previous prime is 22515439. The next prime is 22515461. The reversal of 22515440 is 4451522.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34154 + ... + 34806.

Almost surely, 2^22515440 is an apocalyptic number.

22515440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22515440 is an abundant number, since it is smaller than the sum of its proper divisors (30034768).

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

22515440 is a wasteful number, since it uses less digits than its factorization.

22515440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097 (or 1091 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 22515440 is about 4745.0437300409. The cubic root of 22515440 is about 282.3753698823.

Adding to 22515440 its reverse (4451522), we get a palindrome (26966962).

The spelling of 22515440 in words is "twenty-two million, five hundred fifteen thousand, four hundred forty".