999999999999777 has 64 divisors (see below), whose sum is σ = 1566588736176128. Its totient is φ = 555418008288000.

The previous prime is 999999999999659. The next prime is 999999999999809. The reversal of 999999999999777 is 777999999999999.

It is not a de Polignac number, because 999999999999777 - 2⁸ = 999999999999521 is a prime.

It is a super-9 number, since 9×999999999999777⁹ (a number of 136 digits) contains 999999999 as substring.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (999999999999577) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5705688327 + ... + 5705863587.

It is an arithmetic number, because the mean of its divisors is an integer number (24477949002752).

Almost surely, 2^{999999999999777} is an apocalyptic number.

It is an amenable number.

999999999999777 is a deficient number, since it is larger than the sum of its proper divisors (566588736176351).

999999999999777 is a wasteful number, since it uses less digits than its factorization.

999999999999777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182750.

The product of its digits is 96873331012983, while the sum is 129.

The spelling of 999999999999777 in words is "nine hundred ninety-nine trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, seven hundred seventy-seven".