381523421 has 2 divisors, whose sum is σ = 381523422. Its totient is φ = 381523420.

The previous prime is 381523381. The next prime is 381523427. The reversal of 381523421 is 124325183.

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., 369062521 + 12460900 = 19211^2 + 3530^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-381523421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (381523427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190761710 + 190761711.

It is an arithmetic number, because the mean of its divisors is an integer number (190761711).

Almost surely, 2^381523421 is an apocalyptic number.

It is an amenable number.

381523421 is a deficient number, since it is larger than the sum of its proper divisors (1).

381523421 is an equidigital number, since it uses as much as digits as its factorization.

381523421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5760, while the sum is 29.

The square root of 381523421 is about 19532.6245292331. The cubic root of 381523421 is about 725.2822815171.

The spelling of 381523421 in words is "three hundred eighty-one million, five hundred twenty-three thousand, four hundred twenty-one".