77994449977 has 4 divisors (see below), whose sum is σ = 78766672356. Its totient is φ = 77222227600.

The previous prime is 77994449971. The next prime is 77994449993.

77994449977 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 74411110656 + 3583339321 = 272784^2 + 59861^2 .

It is a cyclic number.

It is not a de Polignac number, because 77994449977 - 2³¹ = 75846966329 is a prime.

It is a super-3 number, since 3×77994449977³ (a number of 34 digits) contains 333 as substring.

It is a Duffinian number.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (77994449971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 386111038 + ... + 386111239.

It is an arithmetic number, because the mean of its divisors is an integer number (19691668089).

Almost surely, 2^77994449977 is an apocalyptic number.

It is an amenable number.

77994449977 is a deficient number, since it is larger than the sum of its proper divisors (772222379).

77994449977 is a wasteful number, since it uses less digits than its factorization.

77994449977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772222378.

The product of its digits is 1008189504, while the sum is 76.

It can be divided in two parts, 779944 and 49977, that added together give a square (829921 = 911²).

The spelling of 77994449977 in words is "seventy-seven billion, nine hundred ninety-four million, four hundred forty-nine thousand, nine hundred seventy-seven".