18916294923881 has 2 divisors, whose sum is σ = 18916294923882. Its totient is φ = 18916294923880.

The previous prime is 18916294923769. The next prime is 18916294923913. The reversal of 18916294923881 is 18832949261981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10673883602281 + 8242411321600 = 3267091^2 + 2870960^2 .

It is an emirp because it is prime and its reverse (18832949261981) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18916294923881 is a prime.

It is a super-2 number, since 2×18916294923881² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18916294913881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9458147461940 + 9458147461941.

It is an arithmetic number, because the mean of its divisors is an integer number (9458147461941).

Almost surely, 2^{18916294923881} is an apocalyptic number.

It is an amenable number.

18916294923881 is a deficient number, since it is larger than the sum of its proper divisors (1).

18916294923881 is an equidigital number, since it uses as much as digits as its factorization.

18916294923881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 107495424, while the sum is 71.

The spelling of 18916294923881 in words is "eighteen trillion, nine hundred sixteen billion, two hundred ninety-four million, nine hundred twenty-three thousand, eight hundred eighty-one".