21249363 has 4 divisors (see below), whose sum is σ = 28332488. Its totient is φ = 14166240.

The previous prime is 21249331. The next prime is 21249443. The reversal of 21249363 is 36394212.

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

It is not a de Polignac number, because 21249363 - 2⁵ = 21249331 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 21249363.

It is not an unprimeable number, because it can be changed into a prime (21249313) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3541558 + ... + 3541563.

It is an arithmetic number, because the mean of its divisors is an integer number (7083122).

Almost surely, 2^21249363 is an apocalyptic number.

21249363 is a deficient number, since it is larger than the sum of its proper divisors (7083125).

21249363 is an equidigital number, since it uses as much as digits as its factorization.

21249363 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7083124.

The product of its digits is 7776, while the sum is 30.

The square root of 21249363 is about 4609.7031357778. The cubic root of 21249363 is about 276.9801451534.

It can be divided in two parts, 21249 and 363, that added together give a palindrome (21612).

The spelling of 21249363 in words is "twenty-one million, two hundred forty-nine thousand, three hundred sixty-three".