31321203231 has 16 divisors (see below), whose sum is σ = 42097881600. Its totient is φ = 20713236288.

The previous prime is 31321203217. The next prime is 31321203253. The reversal of 31321203231 is 13230212313.

It is not a de Polignac number, because 31321203231 - 2¹³ = 31321195039 is a prime.

It is a super-2 number, since 2×31321203231² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31321203198 and 31321203207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31321203271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 148330 + ... + 290936.

It is an arithmetic number, because the mean of its divisors is an integer number (2631117600).

Almost surely, 2^31321203231 is an apocalyptic number.

31321203231 is a deficient number, since it is larger than the sum of its proper divisors (10776678369).

31321203231 is a wasteful number, since it uses less digits than its factorization.

31321203231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143198.

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

Adding to 31321203231 its reverse (13230212313), we get a palindrome (44551415544).

The spelling of 31321203231 in words is "thirty-one billion, three hundred twenty-one million, two hundred three thousand, two hundred thirty-one".