81545217245733 has 4 divisors (see below), whose sum is σ = 108726956327648. Its totient is φ = 54363478163820.

The previous prime is 81545217245647. The next prime is 81545217245749. The reversal of 81545217245733 is 33754271254518.

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 not a de Polignac number, because 81545217245733 - 2⁸ = 81545217245477 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 (81545217245783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13590869540953 + ... + 13590869540958.

It is an arithmetic number, because the mean of its divisors is an integer number (27181739081912).

Almost surely, 2^{81545217245733} is an apocalyptic number.

It is an amenable number.

81545217245733 is a deficient number, since it is larger than the sum of its proper divisors (27181739081915).

81545217245733 is a wasteful number, since it uses less digits than its factorization.

81545217245733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27181739081914.

The product of its digits is 28224000, while the sum is 57.

The spelling of 81545217245733 in words is "eighty-one trillion, five hundred forty-five billion, two hundred seventeen million, two hundred forty-five thousand, seven hundred thirty-three".