18437978969 has 2 divisors, whose sum is σ = 18437978970. Its totient is φ = 18437978968.

The previous prime is 18437978963. The next prime is 18437979019. The reversal of 18437978969 is 96987973481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15566305225 + 2871673744 = 124765^2 + 53588^2 .

It is a cyclic number.

It is not a de Polignac number, because 18437978969 - 2¹⁶ = 18437913433 is a prime.

It is a super-2 number, since 2×18437978969² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18437978963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9218989484 + 9218989485.

It is an arithmetic number, because the mean of its divisors is an integer number (9218989485).

Almost surely, 2^18437978969 is an apocalyptic number.

It is an amenable number.

18437978969 is a deficient number, since it is larger than the sum of its proper divisors (1).

18437978969 is an equidigital number, since it uses as much as digits as its factorization.

18437978969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 164602368, while the sum is 71.

The spelling of 18437978969 in words is "eighteen billion, four hundred thirty-seven million, nine hundred seventy-eight thousand, nine hundred sixty-nine".