1201388778 has 24 divisors (see below), whose sum is σ = 2645683716. Its totient is φ = 393897600.

The previous prime is 1201388777. The next prime is 1201388801. The reversal of 1201388778 is 8778831021.

It can be written as a sum of positive squares in 2 ways, for example, as 1200414609 + 974169 = 34647^2 + 987^2 .

It is not an unprimeable number, because it can be changed into a prime (1201388777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 545983 + ... + 548178.

Almost surely, 2^1201388778 is an apocalyptic number.

1201388778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1201388778 is an abundant number, since it is smaller than the sum of its proper divisors (1444294938).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1201388778 is a wasteful number, since it uses less digits than its factorization.

1201388778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1094230 (or 1094227 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 45.

The square root of 1201388778 is about 34661.0556388579. The cubic root of 1201388778 is about 1063.0683547069.

The spelling of 1201388778 in words is "one billion, two hundred one million, three hundred eighty-eight thousand, seven hundred seventy-eight".