21152291 has 2 divisors, whose sum is σ = 21152292. Its totient is φ = 21152290.

The previous prime is 21152239. The next prime is 21152309. The reversal of 21152291 is 19225112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21152291 - 2²² = 16957987 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21152591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10576145 + 10576146.

It is an arithmetic number, because the mean of its divisors is an integer number (10576146).

Almost surely, 2^21152291 is an apocalyptic number.

21152291 is a deficient number, since it is larger than the sum of its proper divisors (1).

21152291 is an equidigital number, since it uses as much as digits as its factorization.

21152291 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 360, while the sum is 23.

The square root of 21152291 is about 4599.1619888845. The cubic root of 21152291 is about 276.5577315041.

The spelling of 21152291 in words is "twenty-one million, one hundred fifty-two thousand, two hundred ninety-one".