71591029225 has 27 divisors (see below), whose sum is σ = 90402675447. Its totient is φ = 56240022480.

The previous prime is 71591029219. The next prime is 71591029259. The reversal of 71591029225 is 52292019517.

The square root of 71591029225 is 267565.

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., 25772770521 + 45818258704 = 160539^2 + 214052^2 .

It is not a de Polignac number, because 71591029225 - 2³ = 71591029217 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 78931222 + ... + 78932128.

Almost surely, 2^71591029225 is an apocalyptic number.

71591029225 is the 267565-th square number.

71591029225 is the 133783-rd centered octagonal number.

It is an amenable number.

71591029225 is a deficient number, since it is larger than the sum of its proper divisors (18811646222).

71591029225 is an frugal number, since it uses more digits than its factorization.

71591029225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1942 (or 971 counting only the distinct ones).

The product of its (nonzero) digits is 113400, while the sum is 43.

The spelling of 71591029225 in words is "seventy-one billion, five hundred ninety-one million, twenty-nine thousand, two hundred twenty-five".