15945880729 has 9 divisors (see below), whose sum is σ = 16052277661. Its totient is φ = 15840186880.

The previous prime is 15945880649. The next prime is 15945880747. The reversal of 15945880729 is 92708854951.

The square root of 15945880729 is 126277.

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

It can be written as a sum of positive squares in 4 ways, for example, as 12804054025 + 3141826704 = 113155^2 + 56052^2 .

It is not a de Polignac number, because 15945880729 - 2¹⁷ = 15945749657 is a prime.

It is a super-2 number, since 2×15945880729² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15945880789) 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 8 ways as a sum of consecutive naturals, for example, 24876249 + ... + 24876889.

Almost surely, 2^15945880729 is an apocalyptic number.

15945880729 is the 126277-th square number.

15945880729 is the 63139-th centered octagonal number.

It is an amenable number.

15945880729 is a deficient number, since it is larger than the sum of its proper divisors (106396932).

15945880729 is an frugal number, since it uses more digits than its factorization.

15945880729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1676 (or 838 counting only the distinct ones).

The product of its (nonzero) digits is 7257600, while the sum is 58.

The spelling of 15945880729 in words is "fifteen billion, nine hundred forty-five million, eight hundred eighty thousand, seven hundred twenty-nine".