31132231020 has 144 divisors (see below), whose sum is σ = 103145751072. Its totient is φ = 7537950720.

The previous prime is 31132230973. The next prime is 31132231021. The reversal of 31132231020 is 2013223113.

31132231020 is a `hidden beast` number, since 3 + 11 + 322 + 310 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 31132230984 and 31132231002.

It is not an unprimeable number, because it can be changed into a prime (31132231021) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1679724 + ... + 1698156.

It is an arithmetic number, because the mean of its divisors is an integer number (716289938).

Almost surely, 2^31132231020 is an apocalyptic number.

31132231020 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31132231020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (51572875536).

31132231020 is an abundant number, since it is smaller than the sum of its proper divisors (72013520052).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31132231020 is a wasteful number, since it uses less digits than its factorization.

31132231020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19312 (or 19307 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 31132231020 its reverse (2013223113), we get a palindrome (33145454133).

The spelling of 31132231020 in words is "thirty-one billion, one hundred thirty-two million, two hundred thirty-one thousand, twenty".