21654937 has 4 divisors (see below), whose sum is σ = 22596480. Its totient is φ = 20713396.

The previous prime is 21654931. The next prime is 21654943. The reversal of 21654937 is 73945612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (21654931) and next prime (21654943).

It is a cyclic number.

It is not a de Polignac number, because 21654937 - 2¹⁹ = 21130649 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21654896 and 21654905.

It is not an unprimeable number, because it can be changed into a prime (21654931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 470737 + ... + 470782.

It is an arithmetic number, because the mean of its divisors is an integer number (5649120).

Almost surely, 2^21654937 is an apocalyptic number.

It is an amenable number.

21654937 is a deficient number, since it is larger than the sum of its proper divisors (941543).

21654937 is an equidigital number, since it uses as much as digits as its factorization.

21654937 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 941542.

The product of its digits is 45360, while the sum is 37.

The square root of 21654937 is about 4653.4865423680. The cubic root of 21654937 is about 278.7312365795.

The spelling of 21654937 in words is "twenty-one million, six hundred fifty-four thousand, nine hundred thirty-seven".