18491089 has 2 divisors, whose sum is σ = 18491090. Its totient is φ = 18491088.

The previous prime is 18491071. The next prime is 18491107. The reversal of 18491089 is 98019481.

It is a balanced prime because it is at equal distance from previous prime (18491071) and next prime (18491107).

It can be written as a sum of positive squares in only one way, i.e., 18490000 + 1089 = 4300^2 + 33^2 .

It is a cyclic number.

It is not a de Polignac number, because 18491089 - 2⁷ = 18490961 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18491029) 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, 9245544 + 9245545.

It is an arithmetic number, because the mean of its divisors is an integer number (9245545).

Almost surely, 2^18491089 is an apocalyptic number.

It is an amenable number.

18491089 is a deficient number, since it is larger than the sum of its proper divisors (1).

18491089 is an equidigital number, since it uses as much as digits as its factorization.

18491089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 18491089 is about 4300.1266260425. The cubic root of 18491089 is about 264.4361525083.

It can be divided in two parts, 1849 and 1089, that multiplied together give a square (2013561 = 1419²).

The spelling of 18491089 in words is "eighteen million, four hundred ninety-one thousand, eighty-nine".