21866892 has 12 divisors (see below), whose sum is σ = 51022776. Its totient is φ = 7288960.

The previous prime is 21866861. The next prime is 21866893. The reversal of 21866892 is 29866812.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (21866893) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 911109 + ... + 911132.

It is an arithmetic number, because the mean of its divisors is an integer number (4251898).

Almost surely, 2^21866892 is an apocalyptic number.

It is an amenable number.

21866892 is an abundant number, since it is smaller than the sum of its proper divisors (29155884).

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

21866892 is a wasteful number, since it uses less digits than its factorization.

21866892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1822248 (or 1822246 counting only the distinct ones).

The product of its digits is 82944, while the sum is 42.

The square root of 21866892 is about 4676.2048714743. The cubic root of 21866892 is about 279.6376776125.

The spelling of 21866892 in words is "twenty-one million, eight hundred sixty-six thousand, eight hundred ninety-two".