191017073025 has 27 divisors (see below), whose sum is σ = 342144544521. Its totient is φ = 101872275840.

The previous prime is 191017073017. The next prime is 191017073053. The reversal of 191017073025 is 520370710191.

The square root of 191017073025 is 437055.

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 23876739441 + 167140333584 = 154521^2 + 408828^2 .

It is not a de Polignac number, because 191017073025 - 2³ = 191017073017 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 6541257 + ... + 6570393.

Almost surely, 2^191017073025 is an apocalyptic number.

191017073025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

191017073025 is the 437055-th square number.

191017073025 is the 218528-th centered octagonal number.

It is an amenable number.

191017073025 is a deficient number, since it is larger than the sum of its proper divisors (151127471496).

191017073025 is an frugal number, since it uses more digits than its factorization.

191017073025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58290 (or 29145 counting only the distinct ones).

The product of its (nonzero) digits is 13230, while the sum is 36.

Multiplying 191017073025 by its sum of digits (36), we get a square (6876614628900 = 2622330²).

The spelling of 191017073025 in words is "one hundred ninety-one billion, seventeen million, seventy-three thousand, twenty-five".