387745321 has 4 divisors (see below), whose sum is σ = 392102100. Its totient is φ = 383388544.

The previous prime is 387745307. The next prime is 387745349. The reversal of 387745321 is 123547783.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 123547783 = 6053 ⋅20411.

It can be written as a sum of positive squares in 2 ways, for example, as 43086096 + 344659225 = 6564^2 + 18565^2 .

It is a cyclic number.

It is not a de Polignac number, because 387745321 - 2⁵ = 387745289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (387745301) 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 in 3 ways as a sum of consecutive naturals, for example, 2178256 + ... + 2178433.

It is an arithmetic number, because the mean of its divisors is an integer number (98025525).

Almost surely, 2^387745321 is an apocalyptic number.

It is an amenable number.

387745321 is a deficient number, since it is larger than the sum of its proper divisors (4356779).

387745321 is an equidigital number, since it uses as much as digits as its factorization.

387745321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4356778.

The product of its digits is 141120, while the sum is 40.

The square root of 387745321 is about 19691.2498587571. The cubic root of 387745321 is about 729.2036859892.

The spelling of 387745321 in words is "three hundred eighty-seven million, seven hundred forty-five thousand, three hundred twenty-one".