20409406 has 16 divisors (see below), whose sum is σ = 31256064. Its totient is φ = 9992664.

The previous prime is 20409383. The next prime is 20409437. The reversal of 20409406 is 60490402.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29541 + ... + 30223.

It is an arithmetic number, because the mean of its divisors is an integer number (1953504).

Almost surely, 2^20409406 is an apocalyptic number.

20409406 is a deficient number, since it is larger than the sum of its proper divisors (10846658).

20409406 is a wasteful number, since it uses less digits than its factorization.

20409406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 975.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 20409406 is about 4517.6770579580. The cubic root of 20409406 is about 273.2814300945.

Adding to 20409406 its reverse (60490402), we get a palindrome (80899808).

The spelling of 20409406 in words is "twenty million, four hundred nine thousand, four hundred six".