820536778 has 8 divisors (see below), whose sum is σ = 1254028068. Its totient is φ = 402527424.

The previous prime is 820536767. The next prime is 820536779. The reversal of 820536778 is 877635028.

It can be written as a sum of positive squares in 2 ways, for example, as 779358889 + 41177889 = 27917^2 + 6417^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (820536779) 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, 3870351 + ... + 3870562.

Almost surely, 2^820536778 is an apocalyptic number.

820536778 is a deficient number, since it is larger than the sum of its proper divisors (433491290).

820536778 is a wasteful number, since it uses less digits than its factorization.

820536778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7740968.

The product of its (nonzero) digits is 564480, while the sum is 46.

The square root of 820536778 is about 28645.0131436521. The cubic root of 820536778 is about 936.1943531020.

It can be divided in two parts, 82053 and 6778, that added together give a triangular number (88831 = T₄₂₁).

The spelling of 820536778 in words is "eight hundred twenty million, five hundred thirty-six thousand, seven hundred seventy-eight".