18497749 has 2 divisors, whose sum is σ = 18497750. Its totient is φ = 18497748.

The previous prime is 18497747. The next prime is 18497767. The reversal of 18497749 is 94779481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12460900 + 6036849 = 3530^2 + 2457^2 .

It is a cyclic number.

It is not a de Polignac number, because 18497749 - 2¹ = 18497747 is a prime.

Together with 18497747, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18497747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9248874 + 9248875.

It is an arithmetic number, because the mean of its divisors is an integer number (9248875).

Almost surely, 2^18497749 is an apocalyptic number.

It is an amenable number.

18497749 is a deficient number, since it is larger than the sum of its proper divisors (1).

18497749 is an equidigital number, since it uses as much as digits as its factorization.

18497749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 49.

The square root of 18497749 is about 4300.9009521262. The cubic root of 18497749 is about 264.4678963279.

The spelling of 18497749 in words is "eighteen million, four hundred ninety-seven thousand, seven hundred forty-nine".