189393921908 has 6 divisors (see below), whose sum is σ = 331439363346. Its totient is φ = 94696960952.

The previous prime is 189393921883. The next prime is 189393921931. The reversal of 189393921908 is 809129393981.

It can be written as a sum of positive squares in only one way, i.e., 151236987664 + 38156934244 = 388892^2 + 195338^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23674240235 + ... + 23674240242.

It is an arithmetic number, because the mean of its divisors is an integer number (55239893891).

Almost surely, 2^189393921908 is an apocalyptic number.

It is an amenable number.

189393921908 is a deficient number, since it is larger than the sum of its proper divisors (142045441438).

189393921908 is a wasteful number, since it uses less digits than its factorization.

189393921908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47348480481 (or 47348480479 counting only the distinct ones).

The product of its (nonzero) digits is 7558272, while the sum is 62.

The spelling of 189393921908 in words is "one hundred eighty-nine billion, three hundred ninety-three million, nine hundred twenty-one thousand, nine hundred eight".