21145294 has 4 divisors (see below), whose sum is σ = 31717944. Its totient is φ = 10572646.

The previous prime is 21145261. The next prime is 21145301. The reversal of 21145294 is 49254112.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5286322 + ... + 5286325.

It is an arithmetic number, because the mean of its divisors is an integer number (7929486).

Almost surely, 2^21145294 is an apocalyptic number.

21145294 is a deficient number, since it is larger than the sum of its proper divisors (10572650).

21145294 is a wasteful number, since it uses less digits than its factorization.

21145294 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10572649.

The product of its digits is 2880, while the sum is 28.

The square root of 21145294 is about 4598.4012439108. The cubic root of 21145294 is about 276.5272338170.

The spelling of 21145294 in words is "twenty-one million, one hundred forty-five thousand, two hundred ninety-four".