81133351 has 12 divisors (see below), whose sum is σ = 91678608. Its totient is φ = 71632704.

The previous prime is 81133321. The next prime is 81133391. The reversal of 81133351 is 15333118.

It is not a de Polignac number, because 81133351 - 2⁷ = 81133223 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 (81133321) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6550 + ... + 14323.

It is an arithmetic number, because the mean of its divisors is an integer number (7639884).

Almost surely, 2^81133351 is an apocalyptic number.

81133351 is a deficient number, since it is larger than the sum of its proper divisors (10545257).

81133351 is a wasteful number, since it uses less digits than its factorization.

81133351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20922 (or 20909 counting only the distinct ones).

The product of its digits is 1080, while the sum is 25.

The square root of 81133351 is about 9007.4053422725. The cubic root of 81133351 is about 432.9121797052.

Adding to 81133351 its reverse (15333118), we get a palindrome (96466469).

The spelling of 81133351 in words is "eighty-one million, one hundred thirty-three thousand, three hundred fifty-one".