81903073 has 16 divisors (see below), whose sum is σ = 95852160. Its totient is φ = 68530176.

The previous prime is 81903071. The next prime is 81903079. The reversal of 81903073 is 37030918.

It is a cyclic number.

It is not a de Polignac number, because 81903073 - 2¹ = 81903071 is a prime.

It is a super-2 number, since 2×81903073² = 13416226733686658, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81903071) 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, 94918 + ... + 95776.

It is an arithmetic number, because the mean of its divisors is an integer number (5990760).

Almost surely, 2^81903073 is an apocalyptic number.

It is an amenable number.

81903073 is a deficient number, since it is larger than the sum of its proper divisors (13949087).

81903073 is a wasteful number, since it uses less digits than its factorization.

81903073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1176.

The product of its (nonzero) digits is 4536, while the sum is 31.

The square root of 81903073 is about 9050.0316574032. The cubic root of 81903073 is about 434.2769032177.

The spelling of 81903073 in words is "eighty-one million, nine hundred three thousand, seventy-three".