81745158 has 32 divisors (see below), whose sum is σ = 180133632. Its totient is φ = 24524000.

The previous prime is 81745141. The next prime is 81745187. The reversal of 81745158 is 85154718.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 535 + ... + 12797.

It is an arithmetic number, because the mean of its divisors is an integer number (5629176).

Almost surely, 2^81745158 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81745158, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90066816).

81745158 is an abundant number, since it is smaller than the sum of its proper divisors (98388474).

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

81745158 is a wasteful number, since it uses less digits than its factorization.

81745158 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12380.

The product of its digits is 44800, while the sum is 39.

The square root of 81745158 is about 9041.3028928357. The cubic root of 81745158 is about 433.9976179727.

The spelling of 81745158 in words is "eighty-one million, seven hundred forty-five thousand, one hundred fifty-eight".