81364837 has 4 divisors (see below), whose sum is σ = 81591840. Its totient is φ = 81137836.

The previous prime is 81364831. The next prime is 81364847. The reversal of 81364837 is 73846318.

It is the 3683-rd star number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81364837 - 2¹¹ = 81362789 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81364837.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81364831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112963 + ... + 113680.

It is an arithmetic number, because the mean of its divisors is an integer number (20397960).

Almost surely, 2^81364837 is an apocalyptic number.

It is an amenable number.

81364837 is a deficient number, since it is larger than the sum of its proper divisors (227003).

81364837 is a wasteful number, since it uses less digits than its factorization.

81364837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227002.

The product of its digits is 96768, while the sum is 40.

The square root of 81364837 is about 9020.2459500836. The cubic root of 81364837 is about 433.3235105597.

The spelling of 81364837 in words is "eighty-one million, three hundred sixty-four thousand, eight hundred thirty-seven".