18427931 has 2 divisors, whose sum is σ = 18427932. Its totient is φ = 18427930.

The previous prime is 18427921. The next prime is 18427933. The reversal of 18427931 is 13972481.

It is a strong prime.

It is an emirp because it is prime and its reverse (13972481) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18427931 - 2¹⁰ = 18426907 is a prime.

It is a super-2 number, since 2×18427931² = 679177281881522, which contains 22 as substring.

Together with 18427933, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18427891 and 18427900.

It is not a weakly prime, because it can be changed into another prime (18427933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9213965 + 9213966.

It is an arithmetic number, because the mean of its divisors is an integer number (9213966).

Almost surely, 2^18427931 is an apocalyptic number.

18427931 is a deficient number, since it is larger than the sum of its proper divisors (1).

18427931 is an equidigital number, since it uses as much as digits as its factorization.

18427931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12096, while the sum is 35.

The square root of 18427931 is about 4292.7766072788. The cubic root of 18427931 is about 264.1347404863.

The spelling of 18427931 in words is "eighteen million, four hundred twenty-seven thousand, nine hundred thirty-one".