999781427773 has 2 divisors, whose sum is σ = 999781427774. Its totient is φ = 999781427772.

The previous prime is 999781427761. The next prime is 999781427803. The reversal of 999781427773 is 377724187999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 957632516569 + 42148911204 = 978587^2 + 205302^2 .

It is a cyclic number.

It is not a de Polignac number, because 999781427773 - 2⁵ = 999781427741 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 999781427696 and 999781427705.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999781427713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499890713886 + 499890713887.

It is an arithmetic number, because the mean of its divisors is an integer number (499890713887).

Almost surely, 2^999781427773 is an apocalyptic number.

It is an amenable number.

999781427773 is a deficient number, since it is larger than the sum of its proper divisors (1).

999781427773 is an equidigital number, since it uses as much as digits as its factorization.

999781427773 is an evil number, because the sum of its binary digits is even.

The product of its digits is 336063168, while the sum is 73.

The spelling of 999781427773 in words is "nine hundred ninety-nine billion, seven hundred eighty-one million, four hundred twenty-seven thousand, seven hundred seventy-three".