18941222781 has 24 divisors (see below), whose sum is σ = 29572897536. Its totient is φ = 11613106080.

The previous prime is 18941222771. The next prime is 18941222831. The reversal of 18941222781 is 18722214981.

18941222781 is a `hidden beast` number, since 1 + 8 + 9 + 412 + 227 + 8 + 1 = 666.

It is not a de Polignac number, because 18941222781 - 2⁶ = 18941222717 is a prime.

It is a super-2 number, since 2×18941222781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18941222771) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 266985 + ... + 330398.

It is an arithmetic number, because the mean of its divisors is an integer number (1232204064).

Almost surely, 2^18941222781 is an apocalyptic number.

It is an amenable number.

18941222781 is a deficient number, since it is larger than the sum of its proper divisors (10631674755).

18941222781 is a wasteful number, since it uses less digits than its factorization.

18941222781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 597673 (or 597670 counting only the distinct ones).

The product of its digits is 129024, while the sum is 45.

The spelling of 18941222781 in words is "eighteen billion, nine hundred forty-one million, two hundred twenty-two thousand, seven hundred eighty-one".