21360571 has 2 divisors, whose sum is σ = 21360572. Its totient is φ = 21360570.

The previous prime is 21360533. The next prime is 21360587. The reversal of 21360571 is 17506312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21360571 - 2²³ = 12971963 is a prime.

It is not a weakly prime, because it can be changed into another prime (21360371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10680285 + 10680286.

It is an arithmetic number, because the mean of its divisors is an integer number (10680286).

Almost surely, 2^21360571 is an apocalyptic number.

21360571 is a deficient number, since it is larger than the sum of its proper divisors (1).

21360571 is an equidigital number, since it uses as much as digits as its factorization.

21360571 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 21360571 is about 4621.7497768702. The cubic root of 21360571 is about 277.4624941871.

Adding to 21360571 its reverse (17506312), we get a palindrome (38866883).

The spelling of 21360571 in words is "twenty-one million, three hundred sixty thousand, five hundred seventy-one".