21494959 has 2 divisors, whose sum is σ = 21494960. Its totient is φ = 21494958.

The previous prime is 21494929. The next prime is 21494999. The reversal of 21494959 is 95949412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21494959 - 2⁷ = 21494831 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21494929) 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, 10747479 + 10747480.

It is an arithmetic number, because the mean of its divisors is an integer number (10747480).

Almost surely, 2^21494959 is an apocalyptic number.

21494959 is a deficient number, since it is larger than the sum of its proper divisors (1).

21494959 is an equidigital number, since it uses as much as digits as its factorization.

21494959 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 43.

The square root of 21494959 is about 4636.2656308715. The cubic root of 21494959 is about 278.0431544552.

The spelling of 21494959 in words is "twenty-one million, four hundred ninety-four thousand, nine hundred fifty-nine".