18733372409 has 2 divisors, whose sum is σ = 18733372410. Its totient is φ = 18733372408.

The previous prime is 18733372397. The next prime is 18733372451. The reversal of 18733372409 is 90427333781.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17508582400 + 1224790009 = 132320^2 + 34997^2 .

It is an emirp because it is prime and its reverse (90427333781) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18733372409 - 2⁴ = 18733372393 is a prime.

It is not a weakly prime, because it can be changed into another prime (18733372499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9366686204 + 9366686205.

It is an arithmetic number, because the mean of its divisors is an integer number (9366686205).

Almost surely, 2^18733372409 is an apocalyptic number.

It is an amenable number.

18733372409 is a deficient number, since it is larger than the sum of its proper divisors (1).

18733372409 is an equidigital number, since it uses as much as digits as its factorization.

18733372409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 762048, while the sum is 47.

It can be divided in two parts, 18733372 and 409, that added together give a palindrome (18733781).

The spelling of 18733372409 in words is "eighteen billion, seven hundred thirty-three million, three hundred seventy-two thousand, four hundred nine".