20831193 has 12 divisors (see below), whose sum is σ = 31127460. Its totient is φ = 13408416.

The previous prime is 20831183. The next prime is 20831219. The reversal of 20831193 is 39113802.

It can be written as a sum of positive squares in 2 ways, for example, as 17040384 + 3790809 = 4128^2 + 1947^2 .

It is not a de Polignac number, because 20831193 - 2⁴ = 20831177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20831183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39646 + ... + 40167.

It is an arithmetic number, because the mean of its divisors is an integer number (2593955).

Almost surely, 2^20831193 is an apocalyptic number.

It is an amenable number.

20831193 is a deficient number, since it is larger than the sum of its proper divisors (10296267).

20831193 is a wasteful number, since it uses less digits than its factorization.

20831193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79848 (or 79845 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 20831193 is about 4564.1201780847. The cubic root of 20831193 is about 275.1511807852.

Adding to 20831193 its reverse (39113802), we get a palindrome (59944995).

The spelling of 20831193 in words is "twenty million, eight hundred thirty-one thousand, one hundred ninety-three".