81854175622 has 4 divisors (see below), whose sum is σ = 122781263436. Its totient is φ = 40927087810.

The previous prime is 81854175581. The next prime is 81854175643. The reversal of 81854175622 is 22657145818.

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

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20463543904 + ... + 20463543907.

It is an arithmetic number, because the mean of its divisors is an integer number (30695315859).

Almost surely, 2^81854175622 is an apocalyptic number.

81854175622 is a deficient number, since it is larger than the sum of its proper divisors (40927087814).

81854175622 is a wasteful number, since it uses less digits than its factorization.

81854175622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40927087813.

The product of its digits is 1075200, while the sum is 49.

The spelling of 81854175622 in words is "eighty-one billion, eight hundred fifty-four million, one hundred seventy-five thousand, six hundred twenty-two".