22181780 has 24 divisors (see below), whose sum is σ = 47222952. Its totient is φ = 8750592.

The previous prime is 22181777. The next prime is 22181801. The reversal of 22181780 is 8718122.

It can be written as a sum of positive squares in 4 ways, for example, as 8844676 + 13337104 = 2974^2 + 3652^2 .

It is a congruent number.

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 in 7 ways as a sum of consecutive naturals, for example, 6137 + ... + 9056.

It is an arithmetic number, because the mean of its divisors is an integer number (1967623).

Almost surely, 2^22181780 is an apocalyptic number.

22181780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22181780 is an abundant number, since it is smaller than the sum of its proper divisors (25041172).

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

22181780 is a wasteful number, since it uses less digits than its factorization.

22181780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15275 (or 15273 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 22181780 is about 4709.7537090595. The cubic root of 22181780 is about 280.9735667439.

The spelling of 22181780 in words is "twenty-two million, one hundred eighty-one thousand, seven hundred eighty".