388573921 has 4 divisors (see below), whose sum is σ = 409025200. Its totient is φ = 368122644.

The previous prime is 388573909. The next prime is 388573931. The reversal of 388573921 is 129375883.

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 not a de Polignac number, because 388573921 - 2¹³ = 388565729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (388573931) 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, 10225611 + ... + 10225648.

It is an arithmetic number, because the mean of its divisors is an integer number (102256300).

Almost surely, 2^388573921 is an apocalyptic number.

It is an amenable number.

388573921 is a deficient number, since it is larger than the sum of its proper divisors (20451279).

388573921 is a wasteful number, since it uses less digits than its factorization.

388573921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20451278.

The product of its digits is 362880, while the sum is 46.

The square root of 388573921 is about 19712.2784324897. The cubic root of 388573921 is about 729.7227451526.

It can be divided in two parts, 38857 and 3921, that added together give a triangular number (42778 = T₂₉₂).

The spelling of 388573921 in words is "three hundred eighty-eight million, five hundred seventy-three thousand, nine hundred twenty-one".