11355557778 has 32 divisors (see below), whose sum is σ = 25580260800. Its totient is φ = 3733332768.

The previous prime is 11355557749. The next prime is 11355557797. The reversal of 11355557778 is 87775555311.

11355557778 is a `hidden beast` number, since 1 + 13 + 5 + 5 + 557 + 7 + 78 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a plaindrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1436388 + ... + 1444271.

It is an arithmetic number, because the mean of its divisors is an integer number (799383150).

Almost surely, 2^11355557778 is an apocalyptic number.

11355557778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

11355557778 is an abundant number, since it is smaller than the sum of its proper divisors (14224703022).

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

11355557778 is a wasteful number, since it uses less digits than its factorization.

11355557778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2880743 (or 2880737 counting only the distinct ones).

The product of its digits is 5145000, while the sum is 54.

The spelling of 11355557778 in words is "eleven billion, three hundred fifty-five million, five hundred fifty-seven thousand, seven hundred seventy-eight".