20313131 has 8 divisors (see below), whose sum is σ = 20647440. Its totient is φ = 19981728.

The previous prime is 20313121. The next prime is 20313133. The reversal of 20313131 is 13131302.

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

It is a cyclic number.

It is not a de Polignac number, because 20313131 - 2⁶ = 20313067 is a prime.

It is a super-2 number, since 2×20313131² = 825246582046322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20313133) 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, 16520 + ... + 17706.

It is an arithmetic number, because the mean of its divisors is an integer number (2580930).

Almost surely, 2^20313131 is an apocalyptic number.

20313131 is a deficient number, since it is larger than the sum of its proper divisors (334309).

20313131 is a wasteful number, since it uses less digits than its factorization.

20313131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1453.

The product of its (nonzero) digits is 54, while the sum is 14.

The square root of 20313131 is about 4507.0090969511. The cubic root of 20313131 is about 272.8510460444.

Adding to 20313131 its reverse (13131302), we get a palindrome (33444433).

The spelling of 20313131 in words is "twenty million, three hundred thirteen thousand, one hundred thirty-one".