1996780777 has 4 divisors (see below), whose sum is σ = 2034455940. Its totient is φ = 1959105616.

The previous prime is 1996780769. The next prime is 1996780789. The reversal of 1996780777 is 7770876991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7770876991 = 23 ⋅337864217.

It can be written as a sum of positive squares in 2 ways, for example, as 1566259776 + 430521001 = 39576^2 + 20749^2 .

It is a cyclic number.

It is not a de Polignac number, because 1996780777 - 2³ = 1996780769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1996700777) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18837502 + ... + 18837607.

It is an arithmetic number, because the mean of its divisors is an integer number (508613985).

Almost surely, 2^1996780777 is an apocalyptic number.

It is an amenable number.

1996780777 is a deficient number, since it is larger than the sum of its proper divisors (37675163).

1996780777 is an equidigital number, since it uses as much as digits as its factorization.

1996780777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37675162.

The product of its (nonzero) digits is 9335088, while the sum is 61.

The square root of 1996780777 is about 44685.3530477269. The cubic root of 1996780777 is about 1259.2446924037.

The spelling of 1996780777 in words is "one billion, nine hundred ninety-six million, seven hundred eighty thousand, seven hundred seventy-seven".