21855654 has 24 divisors (see below), whose sum is σ = 47441160. Its totient is φ = 7271808.

The previous prime is 21855649. The next prime is 21855671. The reversal of 21855654 is 45655812.

It is a super-2 number, since 2×21855654² = 955339223535432, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16069 + ... + 17375.

It is an arithmetic number, because the mean of its divisors is an integer number (1976715).

Almost surely, 2^21855654 is an apocalyptic number.

21855654 is an abundant number, since it is smaller than the sum of its proper divisors (25585506).

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

21855654 is a wasteful number, since it uses less digits than its factorization.

21855654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2244 (or 2241 counting only the distinct ones).

The product of its digits is 48000, while the sum is 36.

The square root of 21855654 is about 4675.0031016032. The cubic root of 21855654 is about 279.5897648939.

The spelling of 21855654 in words is "twenty-one million, eight hundred fifty-five thousand, six hundred fifty-four".