18989756069 has 2 divisors, whose sum is σ = 18989756070. Its totient is φ = 18989756068.

The previous prime is 18989756039. The next prime is 18989756077. The reversal of 18989756069 is 96065798981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14747187844 + 4242568225 = 121438^2 + 65135^2 .

It is a cyclic number.

It is not a de Polignac number, because 18989756069 - 2¹² = 18989751973 is a prime.

It is a super-2 number, since 2×18989756069² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18989756039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9494878034 + 9494878035.

It is an arithmetic number, because the mean of its divisors is an integer number (9494878035).

Almost surely, 2^18989756069 is an apocalyptic number.

It is an amenable number.

18989756069 is a deficient number, since it is larger than the sum of its proper divisors (1).

18989756069 is an equidigital number, since it uses as much as digits as its factorization.

18989756069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58786560, while the sum is 68.

The spelling of 18989756069 in words is "eighteen billion, nine hundred eighty-nine million, seven hundred fifty-six thousand, sixty-nine".