21013115 has 8 divisors (see below), whose sum is σ = 25831008. Its totient is φ = 16400320.

The previous prime is 21013103. The next prime is 21013117. The reversal of 21013115 is 51131012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21013115 - 2¹⁰ = 21012091 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 21013115.

It is not an unprimeable number, because it can be changed into a prime (21013117) 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 7 ways as a sum of consecutive naturals, for example, 51047 + ... + 51456.

It is an arithmetic number, because the mean of its divisors is an integer number (3228876).

Almost surely, 2^21013115 is an apocalyptic number.

21013115 is a deficient number, since it is larger than the sum of its proper divisors (4817893).

21013115 is a wasteful number, since it uses less digits than its factorization.

21013115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102549.

The product of its (nonzero) digits is 30, while the sum is 14.

The square root of 21013115 is about 4584.0064354231. The cubic root of 21013115 is about 275.9498394806.

Adding to 21013115 its reverse (51131012), we get a palindrome (72144127).

The spelling of 21013115 in words is "twenty-one million, thirteen thousand, one hundred fifteen".