20939801 has 4 divisors (see below), whose sum is σ = 22171572. Its totient is φ = 19708032.

The previous prime is 20939783. The next prime is 20939803. The reversal of 20939801 is 10893902.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16321600 + 4618201 = 4040^2 + 2149^2 .

It is not a de Polignac number, because 20939801 - 2¹⁰ = 20938777 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20939803) 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, 615860 + ... + 615893.

It is an arithmetic number, because the mean of its divisors is an integer number (5542893).

Almost surely, 2^20939801 is an apocalyptic number.

It is an amenable number.

20939801 is a deficient number, since it is larger than the sum of its proper divisors (1231771).

20939801 is a wasteful number, since it uses less digits than its factorization.

20939801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1231770.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 20939801 is about 4576.0027316425. The cubic root of 20939801 is about 275.6285391778.

The spelling of 20939801 in words is "twenty million, nine hundred thirty-nine thousand, eight hundred one".