390181381 has 2 divisors, whose sum is σ = 390181382. Its totient is φ = 390181380.

The previous prime is 390181349. The next prime is 390181403. The reversal of 390181381 is 183181093.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 386908900 + 3272481 = 19670^2 + 1809^2 .

It is an emirp because it is prime and its reverse (183181093) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 390181381 - 2⁵ = 390181349 is a prime.

It is a super-2 number, since 2×390181381² = 304483020158134322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (390185381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195090690 + 195090691.

It is an arithmetic number, because the mean of its divisors is an integer number (195090691).

Almost surely, 2^390181381 is an apocalyptic number.

It is an amenable number.

390181381 is a deficient number, since it is larger than the sum of its proper divisors (1).

390181381 is an equidigital number, since it uses as much as digits as its factorization.

390181381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 390181381 is about 19753.0094162890. The cubic root of 390181381 is about 730.7276044354.

The spelling of 390181381 in words is "three hundred ninety million, one hundred eighty-one thousand, three hundred eighty-one".