21212231513 has 8 divisors (see below), whose sum is σ = 23143402080. Its totient is φ = 19281525280.

The previous prime is 21212231483. The next prime is 21212231531. The reversal of 21212231513 is 31513221212.

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 21212231513 - 2¹² = 21212227417 is a prime.

It is a super-2 number, since 2×21212231513² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21212231563) 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, 16868 + ... + 206661.

It is an arithmetic number, because the mean of its divisors is an integer number (2892925260).

Almost surely, 2^21212231513 is an apocalyptic number.

It is an amenable number.

21212231513 is a deficient number, since it is larger than the sum of its proper divisors (1931170567).

21212231513 is a wasteful number, since it uses less digits than its factorization.

21212231513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232167.

The product of its digits is 720, while the sum is 23.

Adding to 21212231513 its reverse (31513221212), we get a palindrome (52725452725).

The spelling of 21212231513 in words is "twenty-one billion, two hundred twelve million, two hundred thirty-one thousand, five hundred thirteen".