11778780 has 48 divisors (see below), whose sum is σ = 35519904. Its totient is φ = 2899200.

The previous prime is 11778763. The next prime is 11778787. The reversal of 11778780 is 8787711.

Added to its reverse (8787711) it gives a triangular number (20566491 = T₆₄₁₃).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11778787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6771 + ... + 8330.

It is an arithmetic number, because the mean of its divisors is an integer number (739998).

Almost surely, 2^11778780 is an apocalyptic number.

11778780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11778780 is an abundant number, since it is smaller than the sum of its proper divisors (23741124).

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

11778780 is a wasteful number, since it uses less digits than its factorization.

11778780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15126 (or 15124 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 39.

The square root of 11778780 is about 3432.0227271975. The cubic root of 11778780 is about 227.5272599465.

Adding to 11778780 its reverse (8787711), we get a triangular number (20566491 = T₆₄₁₃).

The spelling of 11778780 in words is "eleven million, seven hundred seventy-eight thousand, seven hundred eighty".