21034015 has 16 divisors (see below), whose sum is σ = 26943840. Its totient is φ = 15708160.

The previous prime is 21034003. The next prime is 21034033. The reversal of 21034015 is 51043012.

It is not a de Polignac number, because 21034015 - 2¹⁵ = 21001247 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21034015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10191 + ... + 12079.

It is an arithmetic number, because the mean of its divisors is an integer number (1683990).

Almost surely, 2^21034015 is an apocalyptic number.

21034015 is a deficient number, since it is larger than the sum of its proper divisors (5909825).

21034015 is a wasteful number, since it uses less digits than its factorization.

21034015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2042.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 21034015 is about 4586.2855340678. The cubic root of 21034015 is about 276.0412972931.

Adding to 21034015 its reverse (51043012), we get a palindrome (72077027).

It can be divided in two parts, 210 and 34015, that added together give a square (34225 = 185²).

The spelling of 21034015 in words is "twenty-one million, thirty-four thousand, fifteen".