387216391 has 2 divisors, whose sum is σ = 387216392. Its totient is φ = 387216390.

The previous prime is 387216353. The next prime is 387216407. The reversal of 387216391 is 193612783.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 387216391 - 2²¹ = 385119239 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (387216301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193608195 + 193608196.

It is an arithmetic number, because the mean of its divisors is an integer number (193608196).

Almost surely, 2^387216391 is an apocalyptic number.

387216391 is a deficient number, since it is larger than the sum of its proper divisors (1).

387216391 is an equidigital number, since it uses as much as digits as its factorization.

387216391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54432, while the sum is 40.

The square root of 387216391 is about 19677.8146906612. The cubic root of 387216391 is about 728.8719620485.

The spelling of 387216391 in words is "three hundred eighty-seven million, two hundred sixteen thousand, three hundred ninety-one".