21119257 has 2 divisors, whose sum is σ = 21119258. Its totient is φ = 21119256.

The previous prime is 21119249. The next prime is 21119269. The reversal of 21119257 is 75291112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16556761 + 4562496 = 4069^2 + 2136^2 .

It is a cyclic number.

It is not a de Polignac number, because 21119257 - 2³ = 21119249 is a prime.

It is not a weakly prime, because it can be changed into another prime (21119207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10559628 + 10559629.

It is an arithmetic number, because the mean of its divisors is an integer number (10559629).

Almost surely, 2^21119257 is an apocalyptic number.

It is an amenable number.

21119257 is a deficient number, since it is larger than the sum of its proper divisors (1).

21119257 is an equidigital number, since it uses as much as digits as its factorization.

21119257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1260, while the sum is 28.

The square root of 21119257 is about 4595.5692792080. The cubic root of 21119257 is about 276.4136877202.

The spelling of 21119257 in words is "twenty-one million, one hundred nineteen thousand, two hundred fifty-seven".