21965351 has 2 divisors, whose sum is σ = 21965352. Its totient is φ = 21965350.

The previous prime is 21965249. The next prime is 21965357. The reversal of 21965351 is 15356912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21965351 - 2¹⁴ = 21948967 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21965357) 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 as a sum of consecutive naturals, namely, 10982675 + 10982676.

It is an arithmetic number, because the mean of its divisors is an integer number (10982676).

Almost surely, 2^21965351 is an apocalyptic number.

21965351 is a deficient number, since it is larger than the sum of its proper divisors (1).

21965351 is an equidigital number, since it uses as much as digits as its factorization.

21965351 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8100, while the sum is 32.

The square root of 21965351 is about 4686.7207085552. The cubic root of 21965351 is about 280.0567529518.

The spelling of 21965351 in words is "twenty-one million, nine hundred sixty-five thousand, three hundred fifty-one".