20009490 has 16 divisors (see below), whose sum is σ = 48022848. Its totient is φ = 5335856.

The previous prime is 20009453. The next prime is 20009497. The reversal of 20009490 is 9490002.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20009490.

It is not an unprimeable number, because it can be changed into a prime (20009497) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 333462 + ... + 333521.

It is an arithmetic number, because the mean of its divisors is an integer number (3001428).

Almost surely, 2^20009490 is an apocalyptic number.

20009490 is an abundant number, since it is smaller than the sum of its proper divisors (28013358).

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

20009490 is a wasteful number, since it uses less digits than its factorization.

20009490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666993.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 20009490 is about 4473.1968434219. The cubic root of 20009490 is about 271.4846879093.

Adding to 20009490 its reverse (9490002), we get a palindrome (29499492).

The spelling of 20009490 in words is "twenty million, nine thousand, four hundred ninety".