21148297 has 2 divisors, whose sum is σ = 21148298. Its totient is φ = 21148296.

The previous prime is 21148277. The next prime is 21148321. The reversal of 21148297 is 79284112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20331081 + 817216 = 4509^2 + 904^2 .

It is a cyclic number.

It is not a de Polignac number, because 21148297 - 2²³ = 12759689 is a prime.

It is not a weakly prime, because it can be changed into another prime (21148207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10574148 + 10574149.

It is an arithmetic number, because the mean of its divisors is an integer number (10574149).

Almost surely, 2^21148297 is an apocalyptic number.

It is an amenable number.

21148297 is a deficient number, since it is larger than the sum of its proper divisors (1).

21148297 is an equidigital number, since it uses as much as digits as its factorization.

21148297 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 34.

The square root of 21148297 is about 4598.7277588481. The cubic root of 21148297 is about 276.5403237583.

The spelling of 21148297 in words is "twenty-one million, one hundred forty-eight thousand, two hundred ninety-seven".