999779999977999 has 2 divisors, whose sum is σ = 999779999978000. Its totient is φ = 999779999977998.

The previous prime is 999779999977973. The next prime is 999779999978041.

999779999977999 is nontrivially palindromic in base 10.

It is a weak prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 999779999977999 - 2¹¹ = 999779999975951 is a prime.

It is a zygodrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999779999917999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499889999988999 + 499889999989000.

It is an arithmetic number, because the mean of its divisors is an integer number (499889999989000).

Almost surely, 2^{999779999977999} is an apocalyptic number.

999779999977999 is a deficient number, since it is larger than the sum of its proper divisors (1).

999779999977999 is an equidigital number, since it uses as much as digits as its factorization.

999779999977999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75345924121209, while the sum is 127.

The spelling of 999779999977999 in words is "nine hundred ninety-nine trillion, seven hundred seventy-nine billion, nine hundred ninety-nine million, nine hundred seventy-seven thousand, nine hundred ninety-nine".