21854965 has 16 divisors (see below), whose sum is σ = 29278656. Its totient is φ = 15523200.

The previous prime is 21854947. The next prime is 21854977. The reversal of 21854965 is 56945812.

It is not a de Polignac number, because 21854965 - 2⁷ = 21854837 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2256 + ... + 6985.

It is an arithmetic number, because the mean of its divisors is an integer number (1829916).

Almost surely, 2^21854965 is an apocalyptic number.

It is an amenable number.

21854965 is a deficient number, since it is larger than the sum of its proper divisors (7423691).

21854965 is a wasteful number, since it uses less digits than its factorization.

21854965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9300.

The product of its digits is 86400, while the sum is 40.

The square root of 21854965 is about 4674.9294112318. The cubic root of 21854965 is about 279.5868268384.

The spelling of 21854965 in words is "twenty-one million, eight hundred fifty-four thousand, nine hundred sixty-five".