18401731 has 2 divisors, whose sum is σ = 18401732. Its totient is φ = 18401730.

The previous prime is 18401717. The next prime is 18401783. The reversal of 18401731 is 13710481.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18401731 - 2¹⁹ = 17877443 is a prime.

It is a super-2 number, since 2×18401731² = 677247407592722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18401696 and 18401705.

It is not a weakly prime, because it can be changed into another prime (18401431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9200865 + 9200866.

It is an arithmetic number, because the mean of its divisors is an integer number (9200866).

Almost surely, 2^18401731 is an apocalyptic number.

18401731 is a deficient number, since it is larger than the sum of its proper divisors (1).

18401731 is an equidigital number, since it uses as much as digits as its factorization.

18401731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 18401731 is about 4289.7238838881. The cubic root of 18401731 is about 264.0095028336.

The spelling of 18401731 in words is "eighteen million, four hundred one thousand, seven hundred thirty-one".