999766667993 has 2 divisors, whose sum is σ = 999766667994. Its totient is φ = 999766667992.

The previous prime is 999766667953. The next prime is 999766668029. The reversal of 999766667993 is 399766667999.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 995229702544 + 4536965449 = 997612^2 + 67357^2 .

It is a cyclic number.

It is not a de Polignac number, because 999766667993 - 2³⁸ = 724888761049 is a prime.

It is not a weakly prime, because it can be changed into another prime (999766667953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499883333996 + 499883333997.

It is an arithmetic number, because the mean of its divisors is an integer number (499883333997).

Almost surely, 2^999766667993 is an apocalyptic number.

It is an amenable number.

999766667993 is a deficient number, since it is larger than the sum of its proper divisors (1).

999766667993 is an equidigital number, since it uses as much as digits as its factorization.

999766667993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11249543088, while the sum is 86.

The spelling of 999766667993 in words is "nine hundred ninety-nine billion, seven hundred sixty-six million, six hundred sixty-seven thousand, nine hundred ninety-three".