21854651 has 16 divisors (see below), whose sum is σ = 27109824. Its totient is φ = 17155584.

The previous prime is 21854641. The next prime is 21854687. The reversal of 21854651 is 15645812.

It is a cyclic number.

It is not a de Polignac number, because 21854651 - 2⁶ = 21854587 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21854611) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11591 + ... + 13343.

It is an arithmetic number, because the mean of its divisors is an integer number (1694364).

Almost surely, 2^21854651 is an apocalyptic number.

21854651 is a deficient number, since it is larger than the sum of its proper divisors (5255173).

21854651 is a wasteful number, since it uses less digits than its factorization.

21854651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1910.

The product of its digits is 9600, while the sum is 32.

The square root of 21854651 is about 4674.8958277164. The cubic root of 21854651 is about 279.5854878493.

The spelling of 21854651 in words is "twenty-one million, eight hundred fifty-four thousand, six hundred fifty-one".