20780190 has 24 divisors (see below), whose sum is σ = 54028728. Its totient is φ = 5541360.

The previous prime is 20780189. The next prime is 20780197. The reversal of 20780190 is 9108702.

It is a super-2 number, since 2×20780190² = 863632592872200, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20780197) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 115356 + ... + 115535.

It is an arithmetic number, because the mean of its divisors is an integer number (2251197).

Almost surely, 2^20780190 is an apocalyptic number.

20780190 is an abundant number, since it is smaller than the sum of its proper divisors (33248538).

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

20780190 is a wasteful number, since it uses less digits than its factorization.

20780190 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230904 (or 230901 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 20780190 is about 4558.5293681186. The cubic root of 20780190 is about 274.9264376241.

Adding to 20780190 its reverse (9108702), we get a palindrome (29888892).

The spelling of 20780190 in words is "twenty million, seven hundred eighty thousand, one hundred ninety".