21149373 has 16 divisors (see below), whose sum is σ = 32299520. Its totient is φ = 12058416.

The previous prime is 21149353. The next prime is 21149383. The reversal of 21149373 is 37394112.

It is not a de Polignac number, because 21149373 - 2⁹ = 21148861 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21149373.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21149333) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12186 + ... + 13812.

It is an arithmetic number, because the mean of its divisors is an integer number (2018720).

Almost surely, 2^21149373 is an apocalyptic number.

It is an amenable number.

21149373 is a deficient number, since it is larger than the sum of its proper divisors (11150147).

21149373 is a wasteful number, since it uses less digits than its factorization.

21149373 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2256.

The product of its digits is 4536, while the sum is 30.

The square root of 21149373 is about 4598.8447462379. The cubic root of 21149373 is about 276.5450136922.

The spelling of 21149373 in words is "twenty-one million, one hundred forty-nine thousand, three hundred seventy-three".