21548291 has 2 divisors, whose sum is σ = 21548292. Its totient is φ = 21548290.

The previous prime is 21548281. The next prime is 21548323. The reversal of 21548291 is 19284512.

It is an a-pointer prime, because the next prime (21548323) can be obtained adding 21548291 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21548291 - 2⁶ = 21548227 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21548201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10774145 + 10774146.

It is an arithmetic number, because the mean of its divisors is an integer number (10774146).

Almost surely, 2^21548291 is an apocalyptic number.

21548291 is a deficient number, since it is larger than the sum of its proper divisors (1).

21548291 is an equidigital number, since it uses as much as digits as its factorization.

21548291 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 32.

The square root of 21548291 is about 4642.0136794284. The cubic root of 21548291 is about 278.2729191867.

The spelling of 21548291 in words is "twenty-one million, five hundred forty-eight thousand, two hundred ninety-one".