18773585777 has 2 divisors, whose sum is σ = 18773585778. Its totient is φ = 18773585776.

The previous prime is 18773585689. The next prime is 18773585837. The reversal of 18773585777 is 77758537781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11129406016 + 7644179761 = 105496^2 + 87431^2 .

It is a cyclic number.

It is not a de Polignac number, because 18773585777 - 2⁸ = 18773585521 is a prime.

It is not a weakly prime, because it can be changed into another prime (18773585177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9386792888 + 9386792889.

It is an arithmetic number, because the mean of its divisors is an integer number (9386792889).

Almost surely, 2^18773585777 is an apocalyptic number.

It is an amenable number.

18773585777 is a deficient number, since it is larger than the sum of its proper divisors (1).

18773585777 is an equidigital number, since it uses as much as digits as its factorization.

18773585777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80673600, while the sum is 65.

The spelling of 18773585777 in words is "eighteen billion, seven hundred seventy-three million, five hundred eighty-five thousand, seven hundred seventy-seven".