81675697601 has 4 divisors (see below), whose sum is σ = 85226814912. Its totient is φ = 78124580292.

The previous prime is 81675697591. The next prime is 81675697603. The reversal of 81675697601 is 10679657618.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81675697601 - 2²² = 81671503297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81675697603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1775558621 + ... + 1775558666.

It is an arithmetic number, because the mean of its divisors is an integer number (21306703728).

Almost surely, 2^81675697601 is an apocalyptic number.

It is an amenable number.

81675697601 is a deficient number, since it is larger than the sum of its proper divisors (3551117311).

81675697601 is a wasteful number, since it uses less digits than its factorization.

81675697601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3551117310.

The product of its (nonzero) digits is 3810240, while the sum is 56.

The spelling of 81675697601 in words is "eighty-one billion, six hundred seventy-five million, six hundred ninety-seven thousand, six hundred one".