81903736 has 64 divisors (see below), whose sum is σ = 168376320. Its totient is φ = 37234560.

The previous prime is 81903733. The next prime is 81903769. The reversal of 81903736 is 63730918.

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 81903695 and 81903704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81903733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 473346 + ... + 473518.

It is an arithmetic number, because the mean of its divisors is an integer number (2630880).

Almost surely, 2^81903736 is an apocalyptic number.

It is an amenable number.

81903736 is an abundant number, since it is smaller than the sum of its proper divisors (86472584).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81903736 is a wasteful number, since it uses less digits than its factorization.

81903736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 81903736 is about 9050.0682870352. The cubic root of 81903736 is about 434.2780750289.

The spelling of 81903736 in words is "eighty-one million, nine hundred three thousand, seven hundred thirty-six".