21030849 has 36 divisors (see below), whose sum is σ = 35757696. Its totient is φ = 11875248.

The previous prime is 21030797. The next prime is 21030857. The reversal of 21030849 is 94803012.

It is not a de Polignac number, because 21030849 - 2⁷ = 21030721 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21030899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 45192 + ... + 45654.

Almost surely, 2^21030849 is an apocalyptic number.

It is an amenable number.

21030849 is a deficient number, since it is larger than the sum of its proper divisors (14726847).

21030849 is a wasteful number, since it uses less digits than its factorization.

21030849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 586 (or 576 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21030849 is about 4585.9403615834. The cubic root of 21030849 is about 276.0274468609.

The spelling of 21030849 in words is "twenty-one million, thirty thousand, eight hundred forty-nine".