81334989357 has 8 divisors (see below), whose sum is σ = 108900405120. Its totient is φ = 53996449920.

The previous prime is 81334989353. The next prime is 81334989377. The reversal of 81334989357 is 75398943318.

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

It is not a de Polignac number, because 81334989357 - 2² = 81334989353 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81334989357.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81334989353) 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, 56718244 + ... + 56719677.

It is an arithmetic number, because the mean of its divisors is an integer number (13612550640).

Almost surely, 2^81334989357 is an apocalyptic number.

It is an amenable number.

81334989357 is a deficient number, since it is larger than the sum of its proper divisors (27565415763).

81334989357 is a wasteful number, since it uses less digits than its factorization.

81334989357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113438163.

The product of its digits is 19595520, while the sum is 60.

The spelling of 81334989357 in words is "eighty-one billion, three hundred thirty-four million, nine hundred eighty-nine thousand, three hundred fifty-seven".