21335949 has 24 divisors (see below), whose sum is σ = 32078592. Its totient is φ = 13654080.

The previous prime is 21335911. The next prime is 21335953. The reversal of 21335949 is 94953312.

It is a happy number.

It is not a de Polignac number, because 21335949 - 2⁹ = 21335437 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21335999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24292 + ... + 25154.

It is an arithmetic number, because the mean of its divisors is an integer number (1336608).

Almost surely, 2^21335949 is an apocalyptic number.

It is an amenable number.

21335949 is a deficient number, since it is larger than the sum of its proper divisors (10742643).

21335949 is a wasteful number, since it uses less digits than its factorization.

21335949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 977 (or 974 counting only the distinct ones).

The product of its digits is 29160, while the sum is 36.

The square root of 21335949 is about 4619.0852990608. The cubic root of 21335949 is about 277.3558442894.

The spelling of 21335949 in words is "twenty-one million, three hundred thirty-five thousand, nine hundred forty-nine".