81500783 has 8 divisors (see below), whose sum is σ = 100308768. Its totient is φ = 64484064.

The previous prime is 81500761. The next prime is 81500801. The reversal of 81500783 is 38700518.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81500783 - 2⁶ = 81500719 is a prime.

It is a super-3 number, since 3×81500783³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81500483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 447716 + ... + 447897.

It is an arithmetic number, because the mean of its divisors is an integer number (12538596).

Almost surely, 2^81500783 is an apocalyptic number.

81500783 is a deficient number, since it is larger than the sum of its proper divisors (18807985).

81500783 is a wasteful number, since it uses less digits than its factorization.

81500783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 895633.

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 81500783 is about 9027.7784088889. The cubic root of 81500783 is about 433.5647114765.

The spelling of 81500783 in words is "eighty-one million, five hundred thousand, seven hundred eighty-three".