81158694 has 8 divisors (see below), whose sum is σ = 162317400. Its totient is φ = 27052896.

The previous prime is 81158687. The next prime is 81158719. The reversal of 81158694 is 49685118.

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

81158694 is an admirable number.

It is a super-2 number, since 2×81158694² = 13173467223571272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6763219 + ... + 6763230.

It is an arithmetic number, because the mean of its divisors is an integer number (20289675).

Almost surely, 2^81158694 is an apocalyptic number.

81158694 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

81158694 is a wasteful number, since it uses less digits than its factorization.

81158694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13526454.

The product of its digits is 69120, while the sum is 42.

The square root of 81158694 is about 9008.8120193508. The cubic root of 81158694 is about 432.9572501606.

The spelling of 81158694 in words is "eighty-one million, one hundred fifty-eight thousand, six hundred ninety-four".