31112002021 has 4 divisors (see below), whose sum is σ = 31127474944. Its totient is φ = 31096529100.

The previous prime is 31112002007. The next prime is 31112002037. The reversal of 31112002021 is 12020021113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12020021113 = 89 ⋅135056417.

It is a cyclic number.

It is not a de Polignac number, because 31112002021 - 2⁹ = 31112001509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31112001992 and 31112002010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31112002121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7733445 + ... + 7737466.

It is an arithmetic number, because the mean of its divisors is an integer number (7781868736).

Almost surely, 2^31112002021 is an apocalyptic number.

It is an amenable number.

31112002021 is a deficient number, since it is larger than the sum of its proper divisors (15472923).

31112002021 is a wasteful number, since it uses less digits than its factorization.

31112002021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15472922.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 31112002021 its reverse (12020021113), we get a palindrome (43132023134).

The spelling of 31112002021 in words is "thirty-one billion, one hundred twelve million, two thousand, twenty-one".