387521 has 4 divisors (see below), whose sum is σ = 389844. Its totient is φ = 385200.

The previous prime is 387509. The next prime is 387529. The reversal of 387521 is 125783.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 172225 + 215296 = 415^2 + 464^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-387521 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (387529) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 890 + ... + 1251.

It is an arithmetic number, because the mean of its divisors is an integer number (97461).

2³⁸⁷⁵²¹ is an apocalyptic number.

It is an amenable number.

387521 is a deficient number, since it is larger than the sum of its proper divisors (2323).

387521 is a wasteful number, since it uses less digits than its factorization.

387521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2322.

The product of its digits is 1680, while the sum is 26.

The square root of 387521 is about 622.5118472768. The cubic root of 387521 is about 72.9063037609.

The spelling of 387521 in words is "three hundred eighty-seven thousand, five hundred twenty-one".