381688451 has 2 divisors, whose sum is σ = 381688452. Its totient is φ = 381688450.

The previous prime is 381688423. The next prime is 381688453. The reversal of 381688451 is 154886183.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-381688451 is a prime.

It is a Sophie Germain prime.

Together with 381688453, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (381688453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190844225 + 190844226.

It is an arithmetic number, because the mean of its divisors is an integer number (190844226).

Almost surely, 2^381688451 is an apocalyptic number.

381688451 is a deficient number, since it is larger than the sum of its proper divisors (1).

381688451 is an equidigital number, since it uses as much as digits as its factorization.

381688451 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 184320, while the sum is 44.

The square root of 381688451 is about 19536.8485432016. The cubic root of 381688451 is about 725.3868413549.

The spelling of 381688451 in words is "three hundred eighty-one million, six hundred eighty-eight thousand, four hundred fifty-one".