20222640 has 60 divisors (see below), whose sum is σ = 67916784. Its totient is φ = 5392512.

The previous prime is 20222621. The next prime is 20222689. The reversal of 20222640 is 4622202.

It is a happy number.

20222640 is a `hidden beast` number, since 2 + 0 + 2 + 22 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13324 + ... + 14763.

Almost surely, 2^20222640 is an apocalyptic number.

20222640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20222640 is an abundant number, since it is smaller than the sum of its proper divisors (47694144).

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

20222640 is a wasteful number, since it uses less digits than its factorization.

20222640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28106 (or 28097 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 20222640 is about 4496.9589724613. The cubic root of 20222640 is about 272.4452770062.

Adding to 20222640 its reverse (4622202), we get a palindrome (24844842).

The spelling of 20222640 in words is "twenty million, two hundred twenty-two thousand, six hundred forty".