126169171209 has 45 divisors (see below), whose sum is σ = 191911956951. Its totient is φ = 82606009680.

The previous prime is 126169171159. The next prime is 126169171213. The reversal of 126169171209 is 902171961621.

The square root of 126169171209 is 355203.

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

126169171209 is a `hidden beast` number, since 1 + 2 + 616 + 9 + 1 + 7 + 1 + 20 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 4102786809 + 122066384400 = 64053^2 + 349380^2 .

It is not a de Polignac number, because 126169171209 - 2¹³ = 126169163017 is a prime.

It is a super-3 number, since 3×126169171209³ (a number of 34 digits) contains 333 as substring.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (126169171279) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 195006124 + ... + 195006770.

Almost surely, 2^126169171209 is an apocalyptic number.

126169171209 is the 355203-rd square number.

126169171209 is the 177602-nd centered octagonal number.

It is an amenable number.

126169171209 is a deficient number, since it is larger than the sum of its proper divisors (65742785742).

126169171209 is an frugal number, since it uses more digits than its factorization.

126169171209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1428 (or 711 counting only the distinct ones).

The product of its (nonzero) digits is 81648, while the sum is 45.

The spelling of 126169171209 in words is "one hundred twenty-six billion, one hundred sixty-nine million, one hundred seventy-one thousand, two hundred nine".