81546230821 has 8 divisors (see below), whose sum is σ = 88969464000. Its totient is φ = 74124654240.

The previous prime is 81546230807. The next prime is 81546230851. The reversal of 81546230821 is 12803264518.

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 81546230821 - 2²⁷ = 81412013093 is a prime.

It is a super-2 number, since 2×81546230821² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81546230851) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 310081 + ... + 509158.

It is an arithmetic number, because the mean of its divisors is an integer number (11121183000).

Almost surely, 2^81546230821 is an apocalyptic number.

It is an amenable number.

81546230821 is a deficient number, since it is larger than the sum of its proper divisors (7423233179).

81546230821 is a wasteful number, since it uses less digits than its factorization.

81546230821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828299.

The product of its (nonzero) digits is 92160, while the sum is 40.

The spelling of 81546230821 in words is "eighty-one billion, five hundred forty-six million, two hundred thirty thousand, eight hundred twenty-one".