31123220313 has 32 divisors (see below), whose sum is σ = 43992115200. Its totient is φ = 19517587200.

The previous prime is 31123220299. The next prime is 31123220321. The reversal of 31123220313 is 31302232113.

It is not a de Polignac number, because 31123220313 - 2⁹ = 31123219801 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31123220313.

It is not an unprimeable number, because it can be changed into a prime (31123220333) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4928428 + ... + 4934738.

It is an arithmetic number, because the mean of its divisors is an integer number (1374753600).

Almost surely, 2^31123220313 is an apocalyptic number.

It is an amenable number.

31123220313 is a deficient number, since it is larger than the sum of its proper divisors (12868894887).

31123220313 is a wasteful number, since it uses less digits than its factorization.

31123220313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6933.

The product of its (nonzero) digits is 648, while the sum is 21.

Adding to 31123220313 its reverse (31302232113), we get a palindrome (62425452426).

The spelling of 31123220313 in words is "thirty-one billion, one hundred twenty-three million, two hundred twenty thousand, three hundred thirteen".