811377778 has 4 divisors (see below), whose sum is σ = 1217066670. Its totient is φ = 405688888.

The previous prime is 811377761. The next prime is 811377817. The reversal of 811377778 is 877773118.

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

It can be written as a sum of positive squares in only one way, i.e., 452540529 + 358837249 = 21273^2 + 18943^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202844443 + ... + 202844446.

Almost surely, 2^811377778 is an apocalyptic number.

811377778 is a deficient number, since it is larger than the sum of its proper divisors (405688892).

811377778 is a wasteful number, since it uses less digits than its factorization.

811377778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405688891.

The product of its digits is 460992, while the sum is 49.

The square root of 811377778 is about 28484.6937494508. The cubic root of 811377778 is about 932.6979803744.

The spelling of 811377778 in words is "eight hundred eleven million, three hundred seventy-seven thousand, seven hundred seventy-eight".