81045070851 has 4 divisors (see below), whose sum is σ = 108060094472. Its totient is φ = 54030047232.

The previous prime is 81045070849. The next prime is 81045070891. The reversal of 81045070851 is 15807054018.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 81045070851 - 2¹ = 81045070849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81045070831) 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, 13507511806 + ... + 13507511811.

It is an arithmetic number, because the mean of its divisors is an integer number (27015023618).

Almost surely, 2^81045070851 is an apocalyptic number.

81045070851 is a deficient number, since it is larger than the sum of its proper divisors (27015023621).

81045070851 is a wasteful number, since it uses less digits than its factorization.

81045070851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27015023620.

The product of its (nonzero) digits is 44800, while the sum is 39.

The spelling of 81045070851 in words is "eighty-one billion, forty-five million, seventy thousand, eight hundred fifty-one".