15873228121 has 15 divisors (see below), whose sum is σ = 16803213711. Its totient is φ = 14994706824.

The previous prime is 15873228109. The next prime is 15873228149. The reversal of 15873228121 is 12182237851.

It is a happy number.

The square root of 15873228121 is 125989.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 11650827721 + 4222400400 = 107939^2 + 64980^2 .

It is not a de Polignac number, because 15873228121 - 2¹⁵ = 15873195353 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15873228101) 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 14 ways as a sum of consecutive naturals, for example, 45481855 + ... + 45482203.

Almost surely, 2^15873228121 is an apocalyptic number.

15873228121 is the 125989-th square number.

15873228121 is the 62995-th centered octagonal number.

It is an amenable number.

15873228121 is a deficient number, since it is larger than the sum of its proper divisors (929985590).

15873228121 is an frugal number, since it uses more digits than its factorization.

15873228121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 774 (or 368 counting only the distinct ones).

The product of its digits is 53760, while the sum is 40.

The spelling of 15873228121 in words is "fifteen billion, eight hundred seventy-three million, two hundred twenty-eight thousand, one hundred twenty-one".