18491071 has 2 divisors, whose sum is σ = 18491072. Its totient is φ = 18491070.

The previous prime is 18491051. The next prime is 18491089. The reversal of 18491071 is 17019481.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18491071 - 2¹⁵ = 18458303 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18491021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9245535 + 9245536.

It is an arithmetic number, because the mean of its divisors is an integer number (9245536).

Almost surely, 2^18491071 is an apocalyptic number.

18491071 is a deficient number, since it is larger than the sum of its proper divisors (1).

18491071 is an equidigital number, since it uses as much as digits as its factorization.

18491071 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 18491071 is about 4300.1245330804. The cubic root of 18491071 is about 264.4360667039.

The spelling of 18491071 in words is "eighteen million, four hundred ninety-one thousand, seventy-one".