81382769 has 8 divisors (see below), whose sum is σ = 87713472. Its totient is φ = 75062160.

The previous prime is 81382753. The next prime is 81382811. The reversal of 81382769 is 96728318.

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 81382769 - 2⁴ = 81382753 is a prime.

It is a super-2 number, since 2×81382769² = 13246310180214722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81382739) 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, 27764 + ... + 30554.

It is an arithmetic number, because the mean of its divisors is an integer number (10964184).

Almost surely, 2^81382769 is an apocalyptic number.

It is an amenable number.

81382769 is a deficient number, since it is larger than the sum of its proper divisors (6330703).

81382769 is a wasteful number, since it uses less digits than its factorization.

81382769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5047.

The product of its digits is 145152, while the sum is 44.

The square root of 81382769 is about 9021.2398815240. The cubic root of 81382769 is about 433.3553416173.

The spelling of 81382769 in words is "eighty-one million, three hundred eighty-two thousand, seven hundred sixty-nine".