187922796989 has 4 divisors (see below), whose sum is σ = 190034289180. Its totient is φ = 185811304800.

The previous prime is 187922796983. The next prime is 187922797033. The reversal of 187922796989 is 989697229781.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 989697229781 = 13 ⋅76130556137.

It can be written as a sum of positive squares in 2 ways, for example, as 100568265625 + 87354531364 = 317125^2 + 295558^2 .

It is a cyclic number.

It is not a de Polignac number, because 187922796989 - 2¹⁶ = 187922731453 is a prime.

It is a super-2 number, since 2×187922796989² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (187922796983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1055745962 + ... + 1055746139.

It is an arithmetic number, because the mean of its divisors is an integer number (47508572295).

Almost surely, 2^187922796989 is an apocalyptic number.

It is an amenable number.

187922796989 is a deficient number, since it is larger than the sum of its proper divisors (2111492191).

187922796989 is an equidigital number, since it uses as much as digits as its factorization.

187922796989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2111492190.

The product of its digits is 493807104, while the sum is 77.

The spelling of 187922796989 in words is "one hundred eighty-seven billion, nine hundred twenty-two million, seven hundred ninety-six thousand, nine hundred eighty-nine".