20909938 has 8 divisors (see below), whose sum is σ = 35845632. Its totient is φ = 8961396.

The previous prime is 20909923. The next prime is 20909939. The reversal of 20909938 is 83990902.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 20909938.

It is not an unprimeable number, because it can be changed into a prime (20909939) 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, 746770 + ... + 746797.

It is an arithmetic number, because the mean of its divisors is an integer number (4480704).

Almost surely, 2^20909938 is an apocalyptic number.

20909938 is a deficient number, since it is larger than the sum of its proper divisors (14935694).

20909938 is a wasteful number, since it uses less digits than its factorization.

20909938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1493576.

The product of its (nonzero) digits is 34992, while the sum is 40.

The square root of 20909938 is about 4572.7385667672. The cubic root of 20909938 is about 275.4974489308.

The spelling of 20909938 in words is "twenty million, nine hundred nine thousand, nine hundred thirty-eight".