21115233415 has 8 divisors (see below), whose sum is σ = 25339754448. Its totient is φ = 16891203840.

The previous prime is 21115233409. The next prime is 21115233437. The reversal of 21115233415 is 51433251112.

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

It is not a de Polignac number, because 21115233415 - 2⁹ = 21115232903 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20601 + ... + 206530.

It is an arithmetic number, because the mean of its divisors is an integer number (3167469306).

Almost surely, 2^21115233415 is an apocalyptic number.

21115233415 is a deficient number, since it is larger than the sum of its proper divisors (4224521033).

21115233415 is a wasteful number, since it uses less digits than its factorization.

21115233415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245729.

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

Adding to 21115233415 its reverse (51433251112), we get a palindrome (72548484527).

The spelling of 21115233415 in words is "twenty-one billion, one hundred fifteen million, two hundred thirty-three thousand, four hundred fifteen".