387381021 has 4 divisors (see below), whose sum is σ = 516508032. Its totient is φ = 258254012.

The previous prime is 387380993. The next prime is 387381031. The reversal of 387381021 is 120183783.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 387381021 - 2⁶ = 387380957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (387381031) 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, 64563501 + ... + 64563506.

It is an arithmetic number, because the mean of its divisors is an integer number (129127008).

Almost surely, 2^387381021 is an apocalyptic number.

It is an amenable number.

387381021 is a deficient number, since it is larger than the sum of its proper divisors (129127011).

387381021 is a wasteful number, since it uses less digits than its factorization.

387381021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129127010.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 387381021 is about 19681.9973833958. The cubic root of 387381021 is about 728.9752438243.

The spelling of 387381021 in words is "three hundred eighty-seven million, three hundred eighty-one thousand, twenty-one".