20130831 has 24 divisors (see below), whose sum is σ = 33864480. Its totient is φ = 11284416.

The previous prime is 20130829. The next prime is 20130833. The reversal of 20130831 is 13803102.

It is an interprime number because it is at equal distance from previous prime (20130829) and next prime (20130833).

It is not a de Polignac number, because 20130831 - 2¹ = 20130829 is a prime.

It is a super-3 number, since 3×20130831³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20130833) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 325 + ... + 6353.

It is an arithmetic number, because the mean of its divisors is an integer number (1411020).

Almost surely, 2^20130831 is an apocalyptic number.

20130831 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20130831 is a deficient number, since it is larger than the sum of its proper divisors (13733649).

20130831 is a wasteful number, since it uses less digits than its factorization.

20130831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6095 (or 6092 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20130831 is about 4486.7394620147. The cubic root of 20130831 is about 272.0323590034.

Adding to 20130831 its reverse (13803102), we get a palindrome (33933933).

The spelling of 20130831 in words is "twenty million, one hundred thirty thousand, eight hundred thirty-one".