21234252215 has 16 divisors (see below), whose sum is σ = 27937267200. Its totient is φ = 15365481120.

The previous prime is 21234252157. The next prime is 21234252223. The reversal of 21234252215 is 51225243212.

It is a happy number.

It is not a de Polignac number, because 21234252215 - 2¹⁰ = 21234251191 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 959099 + ... + 980988.

It is an arithmetic number, because the mean of its divisors is an integer number (1746079200).

Almost surely, 2^21234252215 is an apocalyptic number.

21234252215 is a deficient number, since it is larger than the sum of its proper divisors (6703014985).

21234252215 is a wasteful number, since it uses less digits than its factorization.

21234252215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1940302.

The product of its digits is 9600, while the sum is 29.

Adding to 21234252215 its reverse (51225243212), we get a palindrome (72459495427).

The spelling of 21234252215 in words is "twenty-one billion, two hundred thirty-four million, two hundred fifty-two thousand, two hundred fifteen".