21294492 has 12 divisors (see below), whose sum is σ = 49687176. Its totient is φ = 7098160.

The previous prime is 21294491. The next prime is 21294517. The reversal of 21294492 is 29449212.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21294491) 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 3 ways as a sum of consecutive naturals, for example, 887259 + ... + 887282.

It is an arithmetic number, because the mean of its divisors is an integer number (4140598).

Almost surely, 2^21294492 is an apocalyptic number.

It is an amenable number.

21294492 is an abundant number, since it is smaller than the sum of its proper divisors (28392684).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21294492 is a wasteful number, since it uses less digits than its factorization.

21294492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1774548 (or 1774546 counting only the distinct ones).

The product of its digits is 10368, while the sum is 33.

The square root of 21294492 is about 4614.5955402397. The cubic root of 21294492 is about 277.1760882572.

The spelling of 21294492 in words is "twenty-one million, two hundred ninety-four thousand, four hundred ninety-two".