81535189 has 8 divisors (see below), whose sum is σ = 82818560. Its totient is φ = 80258256.

The previous prime is 81535187. The next prime is 81535217. The reversal of 81535189 is 98153518.

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

It is a cyclic number.

It is not a de Polignac number, because 81535189 - 2¹ = 81535187 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 (81535187) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28084 + ... + 30850.

It is an arithmetic number, because the mean of its divisors is an integer number (10352320).

Almost surely, 2^81535189 is an apocalyptic number.

It is an amenable number.

81535189 is a deficient number, since it is larger than the sum of its proper divisors (1283371).

81535189 is a wasteful number, since it uses less digits than its factorization.

81535189 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3219.

The product of its digits is 43200, while the sum is 40.

The square root of 81535189 is about 9029.6837707641. The cubic root of 81535189 is about 433.6257134623.

The spelling of 81535189 in words is "eighty-one million, five hundred thirty-five thousand, one hundred eighty-nine".