21996843 has 16 divisors (see below), whose sum is σ = 32140800. Its totient is φ = 13270880.

The previous prime is 21996841. The next prime is 21996853. The reversal of 21996843 is 34869912.

It is a cyclic number.

It is not a de Polignac number, because 21996843 - 2¹ = 21996841 is a prime.

It is a super-2 number, since 2×21996843² = 967722203933298, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21996795 and 21996804.

It is not an unprimeable number, because it can be changed into a prime (21996841) 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, 6493 + ... + 9281.

It is an arithmetic number, because the mean of its divisors is an integer number (2008800).

Almost surely, 2^21996843 is an apocalyptic number.

21996843 is a deficient number, since it is larger than the sum of its proper divisors (10143957).

21996843 is a wasteful number, since it uses less digits than its factorization.

21996843 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3042.

The product of its digits is 93312, while the sum is 42.

The square root of 21996843 is about 4690.0792104185. The cubic root of 21996843 is about 280.1905293362.

The spelling of 21996843 in words is "twenty-one million, nine hundred ninety-six thousand, eight hundred forty-three".