21831353 has 2 divisors, whose sum is σ = 21831354. Its totient is φ = 21831352.

The previous prime is 21831263. The next prime is 21831371. The reversal of 21831353 is 35313812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19035769 + 2795584 = 4363^2 + 1672^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21831353 is a prime.

It is not a weakly prime, because it can be changed into another prime (21831373) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10915676 + 10915677.

It is an arithmetic number, because the mean of its divisors is an integer number (10915677).

Almost surely, 2^21831353 is an apocalyptic number.

It is an amenable number.

21831353 is a deficient number, since it is larger than the sum of its proper divisors (1).

21831353 is an equidigital number, since it uses as much as digits as its factorization.

21831353 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 26.

The square root of 21831353 is about 4672.4033430345. The cubic root of 21831353 is about 279.4861024641.

The spelling of 21831353 in words is "twenty-one million, eight hundred thirty-one thousand, three hundred fifty-three".