81697528546 has 8 divisors (see below), whose sum is σ = 123230909520. Its totient is φ = 40620558708.

The previous prime is 81697528543. The next prime is 81697528547. The reversal of 81697528546 is 64582579618.

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

It is a super-3 number, since 3×81697528546³ (a number of 34 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (81697528543) 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 3 ways as a sum of consecutive naturals, for example, 114102336 + ... + 114103051.

It is an arithmetic number, because the mean of its divisors is an integer number (15403863690).

Almost surely, 2^81697528546 is an apocalyptic number.

81697528546 is a deficient number, since it is larger than the sum of its proper divisors (41533380974).

81697528546 is a wasteful number, since it uses less digits than its factorization.

81697528546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228205568.

The product of its digits is 29030400, while the sum is 61.

The spelling of 81697528546 in words is "eighty-one billion, six hundred ninety-seven million, five hundred twenty-eight thousand, five hundred forty-six".