31348381 has 4 divisors (see below), whose sum is σ = 31700700. Its totient is φ = 30996064.

The previous prime is 31348351. The next prime is 31348397. The reversal of 31348381 is 18384313.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18384313 = 97 ⋅189529.

It can be written as a sum of positive squares in 2 ways, for example, as 10791225 + 20557156 = 3285^2 + 4534^2 .

It is a cyclic number.

It is not a de Polignac number, because 31348381 - 2⁵ = 31348349 is a prime.

It is a super-2 number, since 2×31348381² = 1965441982642322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31348351) 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, 176026 + ... + 176203.

It is an arithmetic number, because the mean of its divisors is an integer number (7925175).

Almost surely, 2^31348381 is an apocalyptic number.

It is an amenable number.

31348381 is a deficient number, since it is larger than the sum of its proper divisors (352319).

31348381 is an equidigital number, since it uses as much as digits as its factorization.

31348381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352318.

The product of its digits is 6912, while the sum is 31.

The square root of 31348381 is about 5598.9624931767. The cubic root of 31348381 is about 315.3104556594.

The spelling of 31348381 in words is "thirty-one million, three hundred forty-eight thousand, three hundred eighty-one".