189381951890 has 8 divisors (see below), whose sum is σ = 340887513420. Its totient is φ = 75752780752.

The previous prime is 189381951853. The next prime is 189381951911. The reversal of 189381951890 is 98159183981.

It can be written as a sum of positive squares in 2 ways, for example, as 181706965441 + 7674986449 = 426271^2 + 87607^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9469097585 + ... + 9469097604.

Almost surely, 2^189381951890 is an apocalyptic number.

189381951890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

189381951890 is a deficient number, since it is larger than the sum of its proper divisors (151505561530).

189381951890 is a wasteful number, since it uses less digits than its factorization.

189381951890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18938195196.

The product of its (nonzero) digits is 5598720, while the sum is 62.

The spelling of 189381951890 in words is "one hundred eighty-nine billion, three hundred eighty-one million, nine hundred fifty-one thousand, eight hundred ninety".