18726949 has 2 divisors, whose sum is σ = 18726950. Its totient is φ = 18726948.

The previous prime is 18726947. The next prime is 18727001. The reversal of 18726949 is 94962781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17164449 + 1562500 = 4143^2 + 1250^2 .

It is a cyclic number.

It is not a de Polignac number, because 18726949 - 2¹ = 18726947 is a prime.

Together with 18726947, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 18726899 and 18726908.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18726947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9363474 + 9363475.

It is an arithmetic number, because the mean of its divisors is an integer number (9363475).

Almost surely, 2^18726949 is an apocalyptic number.

It is an amenable number.

18726949 is a deficient number, since it is larger than the sum of its proper divisors (1).

18726949 is an equidigital number, since it uses as much as digits as its factorization.

18726949 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 46.

The square root of 18726949 is about 4327.4645001432. The cubic root of 18726949 is about 265.5557294618. Note that the first 3 decimals are identical.

The spelling of 18726949 in words is "eighteen million, seven hundred twenty-six thousand, nine hundred forty-nine".