21214445615 has 16 divisors (see below), whose sum is σ = 28522225440. Its totient is φ = 15011694720.

The previous prime is 21214445587. The next prime is 21214445621. The reversal of 21214445615 is 51654441212.

It is not a de Polignac number, because 21214445615 - 2¹⁰ = 21214444591 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5210360 + ... + 5214429.

It is an arithmetic number, because the mean of its divisors is an integer number (1782639090).

Almost surely, 2^21214445615 is an apocalyptic number.

21214445615 is a deficient number, since it is larger than the sum of its proper divisors (7307779825).

21214445615 is a wasteful number, since it uses less digits than its factorization.

21214445615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10424842.

The product of its digits is 38400, while the sum is 35.

Adding to 21214445615 its reverse (51654441212), we get a palindrome (72868886827).

The spelling of 21214445615 in words is "twenty-one billion, two hundred fourteen million, four hundred forty-five thousand, six hundred fifteen".