31132313320021 has 4 divisors (see below), whose sum is σ = 31132610112492. Its totient is φ = 31132016527552.

The previous prime is 31132313320019. The next prime is 31132313320057. The reversal of 31132313320021 is 12002331323113.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20813531974225 + 10318781345796 = 4562185^2 + 3212286^2 .

It is a cyclic number.

It is not a de Polignac number, because 31132313320021 - 2¹ = 31132313320019 is a prime.

It is a super-3 number, since 3×31132313320021³ (a number of 41 digits) contains 333 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 (31132313329021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 148238836 + ... + 148448701.

It is an arithmetic number, because the mean of its divisors is an integer number (7783152528123).

Almost surely, 2^{31132313320021} is an apocalyptic number.

It is an amenable number.

31132313320021 is a deficient number, since it is larger than the sum of its proper divisors (296792471).

31132313320021 is a wasteful number, since it uses less digits than its factorization.

31132313320021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 296792470.

The product of its (nonzero) digits is 1944, while the sum is 25.

Adding to 31132313320021 its reverse (12002331323113), we get a palindrome (43134644643134).

The spelling of 31132313320021 in words is "thirty-one trillion, one hundred thirty-two billion, three hundred thirteen million, three hundred twenty thousand, twenty-one".