385889821 has 4 divisors (see below), whose sum is σ = 388120572. Its totient is φ = 383659072.

The previous prime is 385889813. The next prime is 385889831. The reversal of 385889821 is 128988583.

It is a happy number.

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 365765625 + 20124196 = 19125^2 + 4486^2 .

It is a cyclic number.

It is not a de Polignac number, because 385889821 - 2³ = 385889813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (385889831) 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, 1115116 + ... + 1115461.

It is an arithmetic number, because the mean of its divisors is an integer number (97030143).

Almost surely, 2^385889821 is an apocalyptic number.

It is an amenable number.

385889821 is a deficient number, since it is larger than the sum of its proper divisors (2230751).

385889821 is a wasteful number, since it uses less digits than its factorization.

385889821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2230750.

The product of its digits is 1105920, while the sum is 52.

The square root of 385889821 is about 19644.0785225472. The cubic root of 385889821 is about 728.0386588626.

The spelling of 385889821 in words is "three hundred eighty-five million, eight hundred eighty-nine thousand, eight hundred twenty-one".