189945978727 has 2 divisors, whose sum is σ = 189945978728. Its totient is φ = 189945978726.

The previous prime is 189945978679. The next prime is 189945978853. The reversal of 189945978727 is 727879549981.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-189945978727 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (189945778727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94972989363 + 94972989364.

It is an arithmetic number, because the mean of its divisors is an integer number (94972989364).

Almost surely, 2^189945978727 is an apocalyptic number.

189945978727 is a deficient number, since it is larger than the sum of its proper divisors (1).

189945978727 is an equidigital number, since it uses as much as digits as its factorization.

189945978727 is an evil number, because the sum of its binary digits is even.

The product of its digits is 640120320, while the sum is 76.

The spelling of 189945978727 in words is "one hundred eighty-nine billion, nine hundred forty-five million, nine hundred seventy-eight thousand, seven hundred twenty-seven".