21494949 has 32 divisors (see below), whose sum is σ = 34504704. Its totient is φ = 11637120.

The previous prime is 21494929. The next prime is 21494959. The reversal of 21494949 is 94949412.

It is not a de Polignac number, because 21494949 - 2⁵ = 21494917 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21494949.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21494929) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 92137 + ... + 92369.

It is an arithmetic number, because the mean of its divisors is an integer number (1078272).

Almost surely, 2^21494949 is an apocalyptic number.

It is an amenable number.

21494949 is a deficient number, since it is larger than the sum of its proper divisors (13009755).

21494949 is a wasteful number, since it uses less digits than its factorization.

21494949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457.

The product of its digits is 93312, while the sum is 42.

The square root of 21494949 is about 4636.2645524172. The cubic root of 21494949 is about 278.0431113377.

The spelling of 21494949 in words is "twenty-one million, four hundred ninety-four thousand, nine hundred forty-nine".