20831393 has 8 divisors (see below), whose sum is σ = 23254176. Its totient is φ = 18496800.

The previous prime is 20831323. The next prime is 20831533. The reversal of 20831393 is 39313802.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20831393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20831323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21548 + ... + 22493.

It is an arithmetic number, because the mean of its divisors is an integer number (2906772).

Almost surely, 2^20831393 is an apocalyptic number.

It is an amenable number.

20831393 is a deficient number, since it is larger than the sum of its proper divisors (2422783).

20831393 is a wasteful number, since it uses less digits than its factorization.

20831393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44095.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 20831393 is about 4564.1420880599. The cubic root of 20831393 is about 275.1520613567.

The spelling of 20831393 in words is "twenty million, eight hundred thirty-one thousand, three hundred ninety-three".