21622680 has 64 divisors (see below), whose sum is σ = 72079200. Its totient is φ = 5765760.

The previous prime is 21622651. The next prime is 21622681. The reversal of 21622680 is 8622612.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21622681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8931 + ... + 11090.

Almost surely, 2^21622680 is an apocalyptic number.

21622680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21622680 is an abundant number, since it is smaller than the sum of its proper divisors (50456520).

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

21622680 is a wasteful number, since it uses less digits than its factorization.

21622680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20041 (or 20031 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 21622680 is about 4650.0193547984. The cubic root of 21622680 is about 278.5927692865.

The spelling of 21622680 in words is "twenty-one million, six hundred twenty-two thousand, six hundred eighty".