81223983901 has 4 divisors (see below), whose sum is σ = 81608931904. Its totient is φ = 80839035900.

The previous prime is 81223983829. The next prime is 81223983917. The reversal of 81223983901 is 10938932218.

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 a cyclic number.

It is not a de Polignac number, because 81223983901 - 2¹³ = 81223975709 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 (81223983931) 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, 192473685 + ... + 192474106.

It is an arithmetic number, because the mean of its divisors is an integer number (20402232976).

Almost surely, 2^81223983901 is an apocalyptic number.

It is an amenable number.

81223983901 is a deficient number, since it is larger than the sum of its proper divisors (384948003).

81223983901 is a wasteful number, since it uses less digits than its factorization.

81223983901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384948002.

The product of its (nonzero) digits is 186624, while the sum is 46.

The spelling of 81223983901 in words is "eighty-one billion, two hundred twenty-three million, nine hundred eighty-three thousand, nine hundred one".