81316263 has 8 divisors (see below), whose sum is σ = 123910528. Its totient is φ = 46466424.

The previous prime is 81316231. The next prime is 81316267. The reversal of 81316263 is 36261318.

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

It is not a de Polignac number, because 81316263 - 2⁵ = 81316231 is a prime.

It is a super-2 number, since 2×81316263² = 13224669256570338, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81316263.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81316267) 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, 1936081 + ... + 1936122.

It is an arithmetic number, because the mean of its divisors is an integer number (15488816).

Almost surely, 2^81316263 is an apocalyptic number.

81316263 is a deficient number, since it is larger than the sum of its proper divisors (42594265).

81316263 is a wasteful number, since it uses less digits than its factorization.

81316263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3872213.

The product of its digits is 5184, while the sum is 30.

The square root of 81316263 is about 9017.5530494697. The cubic root of 81316263 is about 433.2372634498.

The spelling of 81316263 in words is "eighty-one million, three hundred sixteen thousand, two hundred sixty-three".