81501683 has 4 divisors (see below), whose sum is σ = 82020960. Its totient is φ = 80982408.

The previous prime is 81501671. The next prime is 81501691. The reversal of 81501683 is 38610518.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81501683 - 2¹⁸ = 81239539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81501613) 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, 259403 + ... + 259716.

It is an arithmetic number, because the mean of its divisors is an integer number (20505240).

Almost surely, 2^81501683 is an apocalyptic number.

81501683 is a deficient number, since it is larger than the sum of its proper divisors (519277).

81501683 is a wasteful number, since it uses less digits than its factorization.

81501683 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519276.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 81501683 is about 9027.8282549016. The cubic root of 81501683 is about 433.5663073990.

The spelling of 81501683 in words is "eighty-one million, five hundred one thousand, six hundred eighty-three".