21234151615 has 8 divisors (see below), whose sum is σ = 25482206880. Its totient is φ = 16986504672.

The previous prime is 21234151607. The next prime is 21234151639. The reversal of 21234151615 is 51615143212.

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

It is a cyclic number.

It is not a de Polignac number, because 21234151615 - 2³ = 21234151607 is a prime.

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, 27222 + ... + 207868.

It is an arithmetic number, because the mean of its divisors is an integer number (3185275860).

Almost surely, 2^21234151615 is an apocalyptic number.

21234151615 is a deficient number, since it is larger than the sum of its proper divisors (4248055265).

21234151615 is a wasteful number, since it uses less digits than its factorization.

21234151615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204161.

The product of its digits is 7200, while the sum is 31.

Adding to 21234151615 its reverse (51615143212), we get a palindrome (72849294827).

The spelling of 21234151615 in words is "twenty-one billion, two hundred thirty-four million, one hundred fifty-one thousand, six hundred fifteen".