20409760 has 48 divisors (see below), whose sum is σ = 55109376. Its totient is φ = 6997248.

The previous prime is 20409757. The next prime is 20409769. The reversal of 20409760 is 6790402.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (20409769) 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 7 ways as a sum of consecutive naturals, for example, 7992 + ... + 10231.

It is an arithmetic number, because the mean of its divisors is an integer number (1148112).

Almost surely, 2^20409760 is an apocalyptic number.

20409760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20409760 is an abundant number, since it is smaller than the sum of its proper divisors (34699616).

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

20409760 is a wasteful number, since it uses less digits than its factorization.

20409760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18245 (or 18237 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 20409760 is about 4517.7162372154. The cubic root of 20409760 is about 273.2830101024.

The spelling of 20409760 in words is "twenty million, four hundred nine thousand, seven hundred sixty".