189387878085 has 32 divisors (see below), whose sum is σ = 384788071680. Its totient is φ = 86577315264.

The previous prime is 189387878033. The next prime is 189387878131. The reversal of 189387878085 is 580878783981.

189387878085 is a `hidden beast` number, since 18 + 9 + 387 + 87 + 80 + 85 = 666.

It is not a de Polignac number, because 189387878085 - 2⁷ = 189387877957 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 100204282 + ... + 100206171.

It is an arithmetic number, because the mean of its divisors is an integer number (12024627240).

Almost surely, 2^189387878085 is an apocalyptic number.

189387878085 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

189387878085 is an abundant number, since it is smaller than the sum of its proper divisors (195400193595).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

189387878085 is a wasteful number, since it uses less digits than its factorization.

189387878085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200410474 (or 200410468 counting only the distinct ones).

The product of its (nonzero) digits is 216760320, while the sum is 72.

The spelling of 189387878085 in words is "one hundred eighty-nine billion, three hundred eighty-seven million, eight hundred seventy-eight thousand, eighty-five".