31128481831 has 4 divisors (see below), whose sum is σ = 32766823000. Its totient is φ = 29490140664.

The previous prime is 31128481823. The next prime is 31128481843. The reversal of 31128481831 is 13818482113.

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

It is a cyclic number.

It is not a de Polignac number, because 31128481831 - 2³ = 31128481823 is a prime.

It is a super-2 number, since 2×31128481831² (a number of 22 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 (31128481801) 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, 819170556 + ... + 819170593.

It is an arithmetic number, because the mean of its divisors is an integer number (8191705750).

Almost surely, 2^31128481831 is an apocalyptic number.

31128481831 is a deficient number, since it is larger than the sum of its proper divisors (1638341169).

31128481831 is a wasteful number, since it uses less digits than its factorization.

31128481831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1638341168.

The product of its digits is 36864, while the sum is 40.

The spelling of 31128481831 in words is "thirty-one billion, one hundred twenty-eight million, four hundred eighty-one thousand, eight hundred thirty-one".