21113253415 has 8 divisors (see below), whose sum is σ = 25340671008. Its totient is φ = 16887424800.

The previous prime is 21113253407. The next prime is 21113253419. The reversal of 21113253415 is 51435231112.

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

It is not a de Polignac number, because 21113253415 - 2³ = 21113253407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21113253419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 367812 + ... + 421321.

It is an arithmetic number, because the mean of its divisors is an integer number (3167583876).

Almost surely, 2^21113253415 is an apocalyptic number.

21113253415 is a deficient number, since it is larger than the sum of its proper divisors (4227417593).

21113253415 is an equidigital number, since it uses as much as digits as its factorization.

21113253415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 794489.

The product of its digits is 3600, while the sum is 28.

Adding to 21113253415 its reverse (51435231112), we get a palindrome (72548484527).

The spelling of 21113253415 in words is "twenty-one billion, one hundred thirteen million, two hundred fifty-three thousand, four hundred fifteen".