20011231 has 8 divisors (see below), whose sum is σ = 20318400. Its totient is φ = 19706400.

The previous prime is 20011177. The next prime is 20011249. The reversal of 20011231 is 13211002.

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 20011231 - 2¹¹ = 20009183 is a prime.

It is a super-2 number, since 2×20011231² = 800898732270722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011291) 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, 23725 + ... + 24553.

It is an arithmetic number, because the mean of its divisors is an integer number (2539800).

Almost surely, 2^20011231 is an apocalyptic number.

20011231 is a deficient number, since it is larger than the sum of its proper divisors (307169).

20011231 is a wasteful number, since it uses less digits than its factorization.

20011231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1169.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 20011231 is about 4473.3914427423. The cubic root of 20011231 is about 271.4925615255.

Adding to 20011231 its reverse (13211002), we get a palindrome (33222233).

The spelling of 20011231 in words is "twenty million, eleven thousand, two hundred thirty-one".