81193733 has 4 divisors (see below), whose sum is σ = 81284160. Its totient is φ = 81103308.

The previous prime is 81193729. The next prime is 81193741. The reversal of 81193733 is 33739118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81193733 - 2² = 81193729 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81193693 and 81193702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81193793) 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, 43853 + ... + 45666.

It is an arithmetic number, because the mean of its divisors is an integer number (20321040).

Almost surely, 2^81193733 is an apocalyptic number.

It is an amenable number.

81193733 is a deficient number, since it is larger than the sum of its proper divisors (90427).

81193733 is an equidigital number, since it uses as much as digits as its factorization.

81193733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90426.

The product of its digits is 13608, while the sum is 35.

The square root of 81193733 is about 9010.7565165196. The cubic root of 81193733 is about 433.0195487088.

The spelling of 81193733 in words is "eighty-one million, one hundred ninety-three thousand, seven hundred thirty-three".