18793942281 has 9 divisors (see below), whose sum is σ = 27147399591. Its totient is φ = 12529020672.

The previous prime is 18793942261. The next prime is 18793942339. The reversal of 18793942281 is 18224939781.

The square root of 18793942281 is 137091.

It is a perfect power (a square), and thus also a powerful number.

18793942281 is a `hidden beast` number, since 187 + 9 + 39 + 422 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 6690422025 + 12103520256 = 81795^2 + 110016^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 18793942281 - 2¹¹ = 18793940233 is a prime.

It is a super-2 number, since 2×18793942281² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18793942261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 388425 + ... + 434121.

Almost surely, 2^18793942281 is an apocalyptic number.

18793942281 is the 137091-st square number.

18793942281 is the 68546-th centered octagonal number.

It is an amenable number.

18793942281 is a deficient number, since it is larger than the sum of its proper divisors (8353457310).

18793942281 is an frugal number, since it uses more digits than its factorization.

18793942281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91400 (or 45700 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 54.

The spelling of 18793942281 in words is "eighteen billion, seven hundred ninety-three million, nine hundred forty-two thousand, two hundred eighty-one".