21442188 has 24 divisors (see below), whose sum is σ = 50122800. Its totient is φ = 7134400.

The previous prime is 21442163. The next prime is 21442229. The reversal of 21442188 is 88124412.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7138 + ... + 9686.

It is an arithmetic number, because the mean of its divisors is an integer number (2088450).

Almost surely, 2^21442188 is an apocalyptic number.

It is an amenable number.

21442188 is an abundant number, since it is smaller than the sum of its proper divisors (28680612).

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

21442188 is a wasteful number, since it uses less digits than its factorization.

21442188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3257 (or 3255 counting only the distinct ones).

The product of its digits is 4096, while the sum is 30.

The square root of 21442188 is about 4630.5710231029. The cubic root of 21442188 is about 277.8154322407.

The spelling of 21442188 in words is "twenty-one million, four hundred forty-two thousand, one hundred eighty-eight".