612331381 has 4 divisors (see below), whose sum is σ = 648350892. Its totient is φ = 576311872.

The previous prime is 612331367. The next prime is 612331393. The reversal of 612331381 is 183133216.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 296700625 + 315630756 = 17225^2 + 17766^2 .

It is a cyclic number.

It is not a de Polignac number, because 612331381 - 2⁷ = 612331253 is a prime.

It is a super-2 number, since 2×612331381² = 749899440314734322, 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 (612337381) 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, 18009730 + ... + 18009763.

It is an arithmetic number, because the mean of its divisors is an integer number (162087723).

Almost surely, 2^612331381 is an apocalyptic number.

It is an amenable number.

612331381 is a deficient number, since it is larger than the sum of its proper divisors (36019511).

612331381 is a wasteful number, since it uses less digits than its factorization.

612331381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36019510.

The product of its digits is 2592, while the sum is 28.

The square root of 612331381 is about 24745.3304888013. The cubic root of 612331381 is about 849.1716872009.

Adding to 612331381 its reverse (183133216), we get a palindrome (795464597).

The spelling of 612331381 in words is "six hundred twelve million, three hundred thirty-one thousand, three hundred eighty-one".