81433837 has 4 divisors (see below), whose sum is σ = 81452160. Its totient is φ = 81415516.

The previous prime is 81433817. The next prime is 81433853. The reversal of 81433837 is 73833418.

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 81433837 - 2¹¹ = 81431789 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81433796 and 81433805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81433817) 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, 2214 + ... + 12952.

It is an arithmetic number, because the mean of its divisors is an integer number (20363040).

Almost surely, 2^81433837 is an apocalyptic number.

It is an amenable number.

81433837 is a deficient number, since it is larger than the sum of its proper divisors (18323).

81433837 is a wasteful number, since it uses less digits than its factorization.

81433837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18322.

The product of its digits is 48384, while the sum is 37.

The square root of 81433837 is about 9024.0698689671. The cubic root of 81433837 is about 433.4459667109.

The spelling of 81433837 in words is "eighty-one million, four hundred thirty-three thousand, eight hundred thirty-seven".