231220042381 has 2 divisors, whose sum is σ = 231220042382. Its totient is φ = 231220042380.

The previous prime is 231220042379. The next prime is 231220042433. The reversal of 231220042381 is 183240022132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 220280974281 + 10939068100 = 469341^2 + 104590^2 .

It is a cyclic number.

It is not a de Polignac number, because 231220042381 - 2¹ = 231220042379 is a prime.

It is a super-2 number, since 2×231220042381² (a number of 24 digits) contains 22 as substring.

Together with 231220042379, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231220049381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115610021190 + 115610021191.

It is an arithmetic number, because the mean of its divisors is an integer number (115610021191).

Almost surely, 2^231220042381 is an apocalyptic number.

It is an amenable number.

231220042381 is a deficient number, since it is larger than the sum of its proper divisors (1).

231220042381 is an equidigital number, since it uses as much as digits as its factorization.

231220042381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 28.

The spelling of 231220042381 in words is "two hundred thirty-one billion, two hundred twenty million, forty-two thousand, three hundred eighty-one".