81546573 has 8 divisors (see below), whose sum is σ = 109585408. Its totient is φ = 53936064.

The previous prime is 81546559. The next prime is 81546593. The reversal of 81546573 is 37564518.

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

It is not a de Polignac number, because 81546573 - 2⁸ = 81546317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81546503) 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, 106636 + ... + 107397.

It is an arithmetic number, because the mean of its divisors is an integer number (13698176).

Almost surely, 2^81546573 is an apocalyptic number.

It is an amenable number.

81546573 is a deficient number, since it is larger than the sum of its proper divisors (28038835).

81546573 is a wasteful number, since it uses less digits than its factorization.

81546573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214163.

The product of its digits is 100800, while the sum is 39.

The square root of 81546573 is about 9030.3141141380. The cubic root of 81546573 is about 433.6458935647.

The spelling of 81546573 in words is "eighty-one million, five hundred forty-six thousand, five hundred seventy-three".