21622040 has 64 divisors (see below), whose sum is σ = 53580960. Its totient is φ = 7787520.

The previous prime is 21622037. The next prime is 21622061. The reversal of 21622040 is 4022612.

It is a super-2 number, since 2×21622040² = 935025227523200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68924 + ... + 69236.

Almost surely, 2^21622040 is an apocalyptic number.

21622040 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 21622040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26790480).

21622040 is an abundant number, since it is smaller than the sum of its proper divisors (31958920).

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

21622040 is a wasteful number, since it uses less digits than its factorization.

21622040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 492 (or 488 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21622040 is about 4649.9505373713. The cubic root of 21622040 is about 278.5900206119.

Adding to 21622040 its reverse (4022612), we get a palindrome (25644652).

The spelling of 21622040 in words is "twenty-one million, six hundred twenty-two thousand, forty".