20988406 has 8 divisors (see below), whose sum is σ = 31794624. Its totient is φ = 10390200.

The previous prime is 20988403. The next prime is 20988437. The reversal of 20988406 is 60488902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20988403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51750 + ... + 52153.

It is an arithmetic number, because the mean of its divisors is an integer number (3974328).

Almost surely, 2^20988406 is an apocalyptic number.

20988406 is a deficient number, since it is larger than the sum of its proper divisors (10806218).

20988406 is a wasteful number, since it uses less digits than its factorization.

20988406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104006.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 20988406 is about 4581.3105111966. The cubic root of 20988406 is about 275.8416353281.

The spelling of 20988406 in words is "twenty million, nine hundred eighty-eight thousand, four hundred six".