31213241 has 4 divisors (see below), whose sum is σ = 33049332. Its totient is φ = 29377152.

The previous prime is 31213213. The next prime is 31213243. The reversal of 31213241 is 14231213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14231213 = 59 ⋅241207.

It can be written as a sum of positive squares in 2 ways, for example, as 21353641 + 9859600 = 4621^2 + 3140^2 .

It is a cyclic number.

It is not a de Polignac number, because 31213241 - 2¹⁴ = 31196857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1836073 = 31213241 / (3 + 1 + 2 + 1 + 3 + 2 + 4 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31213243) 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, 918020 + ... + 918053.

It is an arithmetic number, because the mean of its divisors is an integer number (8262333).

Almost surely, 2^31213241 is an apocalyptic number.

It is an amenable number.

31213241 is a deficient number, since it is larger than the sum of its proper divisors (1836091).

31213241 is a wasteful number, since it uses less digits than its factorization.

31213241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1836090.

The product of its digits is 144, while the sum is 17.

The square root of 31213241 is about 5586.8811514118. The cubic root of 31213241 is about 314.8567115162.

Adding to 31213241 its reverse (14231213), we get a palindrome (45444454).

The spelling of 31213241 in words is "thirty-one million, two hundred thirteen thousand, two hundred forty-one".