81653829 has 8 divisors (see below), whose sum is σ = 109097280. Its totient is φ = 54323136.

The previous prime is 81653827. The next prime is 81653833. The reversal of 81653829 is 92835618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81653829 - 2¹ = 81653827 is a prime.

It is a super-2 number, since 2×81653829² = 13334695580722482, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81653827) 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, 26484 + ... + 29405.

It is an arithmetic number, because the mean of its divisors is an integer number (13637160).

Almost surely, 2^81653829 is an apocalyptic number.

It is an amenable number.

81653829 is a deficient number, since it is larger than the sum of its proper divisors (27443451).

81653829 is a wasteful number, since it uses less digits than its factorization.

81653829 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56379.

The product of its digits is 103680, while the sum is 42.

The square root of 81653829 is about 9036.2508265320. The cubic root of 81653829 is about 433.8359311736.

It can be divided in two parts, 816 and 53829, that added together give a palindrome (54645).

The spelling of 81653829 in words is "eighty-one million, six hundred fifty-three thousand, eight hundred twenty-nine".