189565322881 has 9 divisors (see below), whose sum is σ = 208370454019. Its totient is φ = 172327757800.

The previous prime is 189565322851. The next prime is 189565322897. The reversal of 189565322881 is 188223565981.

The square root of 189565322881 is 435391.

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., 128743898481 + 60821424400 = 358809^2 + 246620^2 .

It is not a de Polignac number, because 189565322881 - 2¹³ = 189565314689 is a prime.

It is a super-2 number, since 2×189565322881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (189565322851) 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, 4769511 + ... + 4809091.

Almost surely, 2^189565322881 is an apocalyptic number.

189565322881 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

189565322881 is the 435391-st square number.

189565322881 is the 217696-th centered octagonal number.

It is an amenable number.

189565322881 is a deficient number, since it is larger than the sum of its proper divisors (18805131138).

189565322881 is an frugal number, since it uses more digits than its factorization.

189565322881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79184 (or 39592 counting only the distinct ones).

The product of its digits is 8294400, while the sum is 58.

Subtracting from 189565322881 its reverse (188223565981), we obtain a square (1341756900 = 36630²).

The spelling of 189565322881 in words is "one hundred eighty-nine billion, five hundred sixty-five million, three hundred twenty-two thousand, eight hundred eighty-one".