189661424789 has 4 divisors (see below), whose sum is σ = 191539260780. Its totient is φ = 187783588800.

The previous prime is 189661424713. The next prime is 189661424879. The reversal of 189661424789 is 987424166981.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 118243138225 + 71418286564 = 343865^2 + 267242^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-189661424789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189661424489) 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, 938917844 + ... + 938918045.

It is an arithmetic number, because the mean of its divisors is an integer number (47884815195).

Almost surely, 2^189661424789 is an apocalyptic number.

It is an amenable number.

189661424789 is a deficient number, since it is larger than the sum of its proper divisors (1877835991).

189661424789 is a wasteful number, since it uses less digits than its factorization.

189661424789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1877835990.

The product of its digits is 41803776, while the sum is 65.

The spelling of 189661424789 in words is "one hundred eighty-nine billion, six hundred sixty-one million, four hundred twenty-four thousand, seven hundred eighty-nine".