189774368161 has 9 divisors (see below), whose sum is σ = 220761485811. Its totient is φ = 162661130352.

The previous prime is 189774368137. The next prime is 189774368183. The reversal of 189774368161 is 161863477981.

The square root of 189774368161 is 435631.

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., 180986430625 + 8787937536 = 425425^2 + 93744^2 .

It is not a de Polignac number, because 189774368161 - 2¹¹ = 189774366113 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 189774368161.

It is not an unprimeable number, because it can be changed into a prime (189774368461) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3018301 + ... + 3080533.

It is an arithmetic number, because the mean of its divisors is an integer number (24529053979).

Almost surely, 2^189774368161 is an apocalyptic number.

189774368161 is the 435631-st square number.

189774368161 is the 217816-th centered octagonal number.

It is an amenable number.

189774368161 is a deficient number, since it is larger than the sum of its proper divisors (30987117650).

189774368161 is an frugal number, since it uses more digits than its factorization.

189774368161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124480 (or 62240 counting only the distinct ones).

The product of its digits is 12192768, while the sum is 61.

The spelling of 189774368161 in words is "one hundred eighty-nine billion, seven hundred seventy-four million, three hundred sixty-eight thousand, one hundred sixty-one".