81140037 has 16 divisors (see below), whose sum is σ = 118195200. Its totient is φ = 49103600.

The previous prime is 81140029. The next prime is 81140041. The reversal of 81140037 is 73004118.

It is a cyclic number.

It is not a de Polignac number, because 81140037 - 2³ = 81140029 is a prime.

It is a super-2 number, since 2×81140037² = 13167411208722738, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81139989 and 81140016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81140537) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28714 + ... + 31412.

It is an arithmetic number, because the mean of its divisors is an integer number (7387200).

Almost surely, 2^81140037 is an apocalyptic number.

It is an amenable number.

81140037 is a deficient number, since it is larger than the sum of its proper divisors (37055163).

81140037 is a wasteful number, since it uses less digits than its factorization.

81140037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3624.

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 81140037 is about 9007.7764736921. The cubic root of 81140037 is about 432.9240711214.

The spelling of 81140037 in words is "eighty-one million, one hundred forty thousand, thirty-seven".