21622401 has 12 divisors (see below), whose sum is σ = 31284240. Its totient is φ = 14391000.

The previous prime is 21622339. The next prime is 21622417. The reversal of 21622401 is 10422612.

21622401 is a `hidden beast` number, since 2 + 1 + 622 + 40 + 1 = 666.

It is not a de Polignac number, because 21622401 - 2⁷ = 21622273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21622201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5026 + ... + 8276.

It is an arithmetic number, because the mean of its divisors is an integer number (2607020).

Almost surely, 2^21622401 is an apocalyptic number.

It is an amenable number.

21622401 is a deficient number, since it is larger than the sum of its proper divisors (9661839).

21622401 is a wasteful number, since it uses less digits than its factorization.

21622401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3996 (or 3993 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 21622401 is about 4649.9893548265. The cubic root of 21622401 is about 278.5915710428.

The spelling of 21622401 in words is "twenty-one million, six hundred twenty-two thousand, four hundred one".