381728551 has 2 divisors, whose sum is σ = 381728552. Its totient is φ = 381728550.

The previous prime is 381728549. The next prime is 381728579. The reversal of 381728551 is 155827183.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 381728551 - 2¹ = 381728549 is a prime.

Together with 381728549, 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 (381728521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190864275 + 190864276.

It is an arithmetic number, because the mean of its divisors is an integer number (190864276).

Almost surely, 2^381728551 is an apocalyptic number.

381728551 is a deficient number, since it is larger than the sum of its proper divisors (1).

381728551 is an equidigital number, since it uses as much as digits as its factorization.

381728551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 67200, while the sum is 40.

The square root of 381728551 is about 19537.8747820739. The cubic root of 381728551 is about 725.4122433930.

The spelling of 381728551 in words is "three hundred eighty-one million, seven hundred twenty-eight thousand, five hundred fifty-one".