21481886 has 8 divisors (see below), whose sum is σ = 32535984. Its totient is φ = 10636560.

The previous prime is 21481883. The next prime is 21481891. The reversal of 21481886 is 68818412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21481886² = 922942852233992, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21481883) 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, 51935 + ... + 52346.

It is an arithmetic number, because the mean of its divisors is an integer number (4066998).

Almost surely, 2^21481886 is an apocalyptic number.

21481886 is a deficient number, since it is larger than the sum of its proper divisors (11054098).

21481886 is a wasteful number, since it uses less digits than its factorization.

21481886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104386.

The product of its digits is 24576, while the sum is 38.

The square root of 21481886 is about 4634.8555533048. The cubic root of 21481886 is about 277.9867754177.

The spelling of 21481886 in words is "twenty-one million, four hundred eighty-one thousand, eight hundred eighty-six".