18951131 has 2 divisors, whose sum is σ = 18951132. Its totient is φ = 18951130.

The previous prime is 18951071. The next prime is 18951133. The reversal of 18951131 is 13115981.

It is a strong prime.

It is an emirp because it is prime and its reverse (13115981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18951131 - 2²² = 14756827 is a prime.

It is a super-2 number, since 2×18951131² = 718290732358322, which contains 22 as substring.

Together with 18951133, 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 = 18951094 and 18951103.

It is not a weakly prime, because it can be changed into another prime (18951133) 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 as a sum of consecutive naturals, namely, 9475565 + 9475566.

It is an arithmetic number, because the mean of its divisors is an integer number (9475566).

Almost surely, 2^18951131 is an apocalyptic number.

18951131 is a deficient number, since it is larger than the sum of its proper divisors (1).

18951131 is an equidigital number, since it uses as much as digits as its factorization.

18951131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 29.

The square root of 18951131 is about 4353.2896756361. The cubic root of 18951131 is about 266.6111928010.

The spelling of 18951131 in words is "eighteen million, nine hundred fifty-one thousand, one hundred thirty-one".