81113437 has 8 divisors (see below), whose sum is σ = 83859776. Its totient is φ = 78406272.

The previous prime is 81113429. The next prime is 81113449. The reversal of 81113437 is 73431118.

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 81113437 - 2³ = 81113429 is a prime.

It is a super-3 number, since 3×81113437³ (a number of 25 digits) contains 333 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 (81113407) 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, 5553 + ... + 13894.

It is an arithmetic number, because the mean of its divisors is an integer number (10482472).

Almost surely, 2^81113437 is an apocalyptic number.

It is an amenable number.

81113437 is a deficient number, since it is larger than the sum of its proper divisors (2746339).

81113437 is a wasteful number, since it uses less digits than its factorization.

81113437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19587.

The product of its digits is 2016, while the sum is 28.

The square root of 81113437 is about 9006.2998506601. The cubic root of 81113437 is about 432.8767576974.

The spelling of 81113437 in words is "eighty-one million, one hundred thirteen thousand, four hundred thirty-seven".