81283031 has 4 divisors (see below), whose sum is σ = 81319392. Its totient is φ = 81246672.

The previous prime is 81283019. The next prime is 81283039. The reversal of 81283031 is 13038218.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81283031 is a prime.

It is a super-2 number, since 2×81283031² = 13213862257093922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81283039) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14591 + ... + 19376.

It is an arithmetic number, because the mean of its divisors is an integer number (20329848).

Almost surely, 2^81283031 is an apocalyptic number.

81283031 is a deficient number, since it is larger than the sum of its proper divisors (36361).

81283031 is a wasteful number, since it uses less digits than its factorization.

81283031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36360.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 81283031 is about 9015.7102326994. The cubic root of 81283031 is about 433.1782375267.

The spelling of 81283031 in words is "eighty-one million, two hundred eighty-three thousand, thirty-one".