15229781281 has 27 divisors (see below), whose sum is σ = 18147961587. Its totient is φ = 12765426960.

The previous prime is 15229781263. The next prime is 15229781291. The reversal of 15229781281 is 18218792251.

The square root of 15229781281 is 123409.

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., 2252926225 + 12976855056 = 47465^2 + 113916^2 .

It is not a de Polignac number, because 15229781281 - 2⁵ = 15229781249 is a prime.

It is a super-2 number, since 2×15229781281² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15229781221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 17647056 + ... + 17647918.

Almost surely, 2^15229781281 is an apocalyptic number.

15229781281 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

15229781281 is the 123409-th square number.

15229781281 is the 61705-th centered octagonal number.

It is an amenable number.

15229781281 is a deficient number, since it is larger than the sum of its proper divisors (2918180306).

15229781281 is an frugal number, since it uses more digits than its factorization.

15229781281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1774 (or 887 counting only the distinct ones).

The product of its digits is 161280, while the sum is 46.

The spelling of 15229781281 in words is "fifteen billion, two hundred twenty-nine million, seven hundred eighty-one thousand, two hundred eighty-one".