31000313131 has 4 divisors (see below), whose sum is σ = 32000323264. Its totient is φ = 30000303000.

The previous prime is 31000313101. The next prime is 31000313173. The reversal of 31000313131 is 13131300013.

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 31000313131 - 2³³ = 22410378539 is a prime.

It is a super-2 number, since 2×31000313131² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

31000313131 is a modest number, since divided by 313131 gives 31000 as remainder.

It is not an unprimeable number, because it can be changed into a prime (31000313101) 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, 500005020 + ... + 500005081.

It is an arithmetic number, because the mean of its divisors is an integer number (8000080816).

Almost surely, 2^31000313131 is an apocalyptic number.

31000313131 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

31000313131 is a deficient number, since it is larger than the sum of its proper divisors (1000010133).

31000313131 is a wasteful number, since it uses less digits than its factorization.

31000313131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1000010132.

The product of its (nonzero) digits is 81, while the sum is 16.

Adding to 31000313131 its reverse (13131300013), we get a palindrome (44131613144).

The spelling of 31000313131 in words is "thirty-one billion, three hundred thirteen thousand, one hundred thirty-one".