31281993213 has 8 divisors (see below), whose sum is σ = 41713510176. Its totient is φ = 20852569200.

The previous prime is 31281993137. The next prime is 31281993217. The reversal of 31281993213 is 31239918213.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31281993213 - 2¹⁷ = 31281862141 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31281993217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 488023 + ... + 548388.

It is an arithmetic number, because the mean of its divisors is an integer number (5214188772).

Almost surely, 2^31281993213 is an apocalyptic number.

It is an amenable number.

31281993213 is a deficient number, since it is larger than the sum of its proper divisors (10431516963).

31281993213 is a wasteful number, since it uses less digits than its factorization.

31281993213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1046475.

The product of its digits is 69984, while the sum is 42.

The spelling of 31281993213 in words is "thirty-one billion, two hundred eighty-one million, nine hundred ninety-three thousand, two hundred thirteen".