31531413213 has 16 divisors (see below), whose sum is σ = 46756945600. Its totient is φ = 21001258800.

The previous prime is 31531413139. The next prime is 31531413223. The reversal of 31531413213 is 31231413513.

31531413213 is a `hidden beast` number, since 3 + 1 + 5 + 31 + 413 + 213 = 666.

It is not a de Polignac number, because 31531413213 - 2¹⁰ = 31531412189 is a prime.

It is a super-3 number, since 3×31531413213³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31531413223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 517363 + ... + 575088.

It is an arithmetic number, because the mean of its divisors is an integer number (2922309100).

Almost surely, 2^31531413213 is an apocalyptic number.

It is an amenable number.

31531413213 is a deficient number, since it is larger than the sum of its proper divisors (15225532387).

31531413213 is a wasteful number, since it uses less digits than its factorization.

31531413213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1093529 (or 1093523 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

Adding to 31531413213 its reverse (31231413513), we get a palindrome (62762826726).

The spelling of 31531413213 in words is "thirty-one billion, five hundred thirty-one million, four hundred thirteen thousand, two hundred thirteen".