20311111231 has 8 divisors (see below), whose sum is σ = 20429300160. Its totient is φ = 20193199488.

The previous prime is 20311111217. The next prime is 20311111243. The reversal of 20311111231 is 13211111302.

It is a happy number.

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 20311111231 - 2⁹ = 20311110719 is a prime.

It is a super-2 number, since 2×20311111231² (a number of 21 digits) 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 (20311111531) 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, 78595 + ... + 216331.

It is an arithmetic number, because the mean of its divisors is an integer number (2553662520).

Almost surely, 2^20311111231 is an apocalyptic number.

20311111231 is a deficient number, since it is larger than the sum of its proper divisors (118188929).

20311111231 is a wasteful number, since it uses less digits than its factorization.

20311111231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138593.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 20311111231 its reverse (13211111302), we get a palindrome (33522222533).

The spelling of 20311111231 in words is "twenty billion, three hundred eleven million, one hundred eleven thousand, two hundred thirty-one".