22720240 has 20 divisors (see below), whose sum is σ = 52824744. Its totient is φ = 9088064.

The previous prime is 22720237. The next prime is 22720261. The reversal of 22720240 is 4202722.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 141922 + ... + 142081.

Almost surely, 2^22720240 is an apocalyptic number.

22720240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22720240 is an abundant number, since it is smaller than the sum of its proper divisors (30104504).

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

22720240 is a wasteful number, since it uses less digits than its factorization.

22720240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284016 (or 284010 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 19.

The square root of 22720240 is about 4766.5752904995. The cubic root of 22720240 is about 283.2289473214.

Adding to 22720240 its reverse (4202722), we get a palindrome (26922962).

The spelling of 22720240 in words is "twenty-two million, seven hundred twenty thousand, two hundred forty".