21034013 has 16 divisors (see below), whose sum is σ = 28242816. Its totient is φ = 15128640.

The previous prime is 21034003. The next prime is 21034033. The reversal of 21034013 is 31043012.

It is a cyclic number.

It is not a de Polignac number, because 21034013 - 2²⁴ = 4256797 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21034003) 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 15 ways as a sum of consecutive naturals, for example, 9506 + ... + 11507.

It is an arithmetic number, because the mean of its divisors is an integer number (1765176).

Almost surely, 2^21034013 is an apocalyptic number.

It is an amenable number.

21034013 is a deficient number, since it is larger than the sum of its proper divisors (7208803).

21034013 is a wasteful number, since it uses less digits than its factorization.

21034013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21044.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21034013 is about 4586.2853160265. The cubic root of 21034013 is about 276.0412885441.

Adding to 21034013 its reverse (31043012), we get a palindrome (52077025).

It can be divided in two parts, 2103 and 4013, that added together give a palindrome (6116).

The spelling of 21034013 in words is "twenty-one million, thirty-four thousand, thirteen".