388294021 has 8 divisors (see below), whose sum is σ = 412540920. Its totient is φ = 364771008.

The previous prime is 388294001. The next prime is 388294033. The reversal of 388294021 is 120492883.

It can be written as a sum of positive squares in 4 ways, for example, as 268500996 + 119793025 = 16386^2 + 10945^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 388294021 - 2¹⁵ = 388261253 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (388294001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179866 + ... + 182011.

It is an arithmetic number, because the mean of its divisors is an integer number (51567615).

Almost surely, 2^388294021 is an apocalyptic number.

It is an amenable number.

388294021 is a deficient number, since it is larger than the sum of its proper divisors (24246899).

388294021 is a wasteful number, since it uses less digits than its factorization.

388294021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361943.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 388294021 is about 19705.1775175967. The cubic root of 388294021 is about 729.5474902465.

It can be divided in two parts, 3882 and 94021, that added together give a triangular number (97903 = T₄₄₂).

The spelling of 388294021 in words is "three hundred eighty-eight million, two hundred ninety-four thousand, twenty-one".