81145673 has 8 divisors (see below), whose sum is σ = 92816448. Its totient is φ = 69494544.

The previous prime is 81145651. The next prime is 81145717. The reversal of 81145673 is 37654118.

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

It is not a de Polignac number, because 81145673 - 2⁸ = 81145417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81145613) 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, 5390 + ... + 13832.

It is an arithmetic number, because the mean of its divisors is an integer number (11602056).

Almost surely, 2^81145673 is an apocalyptic number.

It is an amenable number.

81145673 is a deficient number, since it is larger than the sum of its proper divisors (11670775).

81145673 is a wasteful number, since it uses less digits than its factorization.

81145673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9823.

The product of its digits is 20160, while the sum is 35.

The square root of 81145673 is about 9008.0893090599. The cubic root of 81145673 is about 432.9340945478.

It can be divided in two parts, 81145 and 673, that added together give a palindrome (81818).

The spelling of 81145673 in words is "eighty-one million, one hundred forty-five thousand, six hundred seventy-three".