81103831 has 8 divisors (see below), whose sum is σ = 83365200. Its totient is φ = 78872640.

The previous prime is 81103823. The next prime is 81103853. The reversal of 81103831 is 13830118.

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 81103831 - 2³ = 81103823 is a prime.

It is a super-2 number, since 2×81103831² = 13155662805753122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81103796 and 81103805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81103861) 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, 2041 + ... + 12898.

It is an arithmetic number, because the mean of its divisors is an integer number (10420650).

Almost surely, 2^81103831 is an apocalyptic number.

81103831 is a deficient number, since it is larger than the sum of its proper divisors (2261369).

81103831 is a wasteful number, since it uses less digits than its factorization.

81103831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15089.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 81103831 is about 9005.7665415000. The cubic root of 81103831 is about 432.8596689616.

Adding to 81103831 its reverse (13830118), we get a palindrome (94933949).

The spelling of 81103831 in words is "eighty-one million, one hundred three thousand, eight hundred thirty-one".