31112482721 has 4 divisors (see below), whose sum is σ = 31115156100. Its totient is φ = 31109809344.

The previous prime is 31112482711. The next prime is 31112482771. The reversal of 31112482721 is 12728421113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12728421113 = 1487 ⋅8559799.

It can be written as a sum of positive squares in 2 ways, for example, as 24574951696 + 6537531025 = 156764^2 + 80855^2 .

It is a cyclic number.

It is not a de Polignac number, because 31112482721 - 2⁶ = 31112482657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31112482711) 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, 1319156 + ... + 1342533.

It is an arithmetic number, because the mean of its divisors is an integer number (7778789025).

Almost surely, 2^31112482721 is an apocalyptic number.

It is an amenable number.

31112482721 is a deficient number, since it is larger than the sum of its proper divisors (2673379).

31112482721 is a wasteful number, since it uses less digits than its factorization.

31112482721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2673378.

The product of its digits is 5376, while the sum is 32.

The spelling of 31112482721 in words is "thirty-one billion, one hundred twelve million, four hundred eighty-two thousand, seven hundred twenty-one".