531355381 has 2 divisors, whose sum is σ = 531355382. Its totient is φ = 531355380.

The previous prime is 531355379. The next prime is 531355397. The reversal of 531355381 is 183553135.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 415792881 + 115562500 = 20391^2 + 10750^2 .

It is a cyclic number.

It is not a de Polignac number, because 531355381 - 2¹ = 531355379 is a prime.

It is a super-2 number, since 2×531355381² = 564677081835310322, which contains 22 as substring.

Together with 531355379, 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 (531355301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265677690 + 265677691.

It is an arithmetic number, because the mean of its divisors is an integer number (265677691).

Almost surely, 2^531355381 is an apocalyptic number.

It is an amenable number.

531355381 is a deficient number, since it is larger than the sum of its proper divisors (1).

531355381 is an equidigital number, since it uses as much as digits as its factorization.

531355381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27000, while the sum is 34.

The square root of 531355381 is about 23051.1470647341. The cubic root of 531355381 is about 809.9564987053.

The spelling of 531355381 in words is "five hundred thirty-one million, three hundred fifty-five thousand, three hundred eighty-one".