21542168 has 48 divisors (see below), whose sum is σ = 43876080. Its totient is φ = 9893312.

The previous prime is 21542167. The next prime is 21542173. The reversal of 21542168 is 86124512.

It is a self number, because there is not a number n which added to its sum of digits gives 21542168.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21542161) 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, 406430 + ... + 406482.

It is an arithmetic number, because the mean of its divisors is an integer number (914085).

Almost surely, 2^21542168 is an apocalyptic number.

It is an amenable number.

21542168 is an abundant number, since it is smaller than the sum of its proper divisors (22333912).

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

21542168 is a wasteful number, since it uses less digits than its factorization.

21542168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176 (or 125 counting only the distinct ones).

The product of its digits is 3840, while the sum is 29.

The square root of 21542168 is about 4641.3541127563. The cubic root of 21542168 is about 278.2465593779.

The spelling of 21542168 in words is "twenty-one million, five hundred forty-two thousand, one hundred sixty-eight".