22143440 has 40 divisors (see below), whose sum is σ = 56166048. Its totient is φ = 8051840.

The previous prime is 22143421. The next prime is 22143449. The reversal of 22143440 is 4434122.

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

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22143449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11702 + ... + 13461.

Almost surely, 2^22143440 is an apocalyptic number.

22143440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22143440 is an abundant number, since it is smaller than the sum of its proper divisors (34022608).

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

22143440 is a wasteful number, since it uses less digits than its factorization.

22143440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25187 (or 25181 counting only the distinct ones).

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

The square root of 22143440 is about 4705.6816721916. The cubic root of 22143440 is about 280.8115908777.

Adding to 22143440 its reverse (4434122), we get a palindrome (26577562).

The spelling of 22143440 in words is "twenty-two million, one hundred forty-three thousand, four hundred forty".