21283091 has 2 divisors, whose sum is σ = 21283092. Its totient is φ = 21283090.

The previous prime is 21283039. The next prime is 21283111. The reversal of 21283091 is 19038212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21283091 - 2¹⁸ = 21020947 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21283091.

It is not a weakly prime, because it can be changed into another prime (21283001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10641545 + 10641546.

It is an arithmetic number, because the mean of its divisors is an integer number (10641546).

Almost surely, 2^21283091 is an apocalyptic number.

21283091 is a deficient number, since it is larger than the sum of its proper divisors (1).

21283091 is an equidigital number, since it uses as much as digits as its factorization.

21283091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 21283091 is about 4613.3600553176. The cubic root of 21283091 is about 277.1266130421.

The spelling of 21283091 in words is "twenty-one million, two hundred eighty-three thousand, ninety-one".