81697583583 has 80 divisors (see below), whose sum is σ = 152274608640. Its totient is φ = 42407323200.

The previous prime is 81697583567. The next prime is 81697583641. The reversal of 81697583583 is 38538579618.

It is not a de Polignac number, because 81697583583 - 2⁴ = 81697583567 is a prime.

It is a super-2 number, since 2×81697583583² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a self number, because there is not a number n which added to its sum of digits gives 81697583583.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81697583083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 9419773 + ... + 9428441.

It is an arithmetic number, because the mean of its divisors is an integer number (1903432608).

Almost surely, 2^81697583583 is an apocalyptic number.

81697583583 is a deficient number, since it is larger than the sum of its proper divisors (70577025057).

81697583583 is a wasteful number, since it uses less digits than its factorization.

81697583583 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10210 (or 10201 counting only the distinct ones).

The product of its digits is 43545600, while the sum is 63.

The spelling of 81697583583 in words is "eighty-one billion, six hundred ninety-seven million, five hundred eighty-three thousand, five hundred eighty-three".