380231821 has 4 divisors (see below), whose sum is σ = 380537500. Its totient is φ = 379926144.

The previous prime is 380231807. The next prime is 380231899. The reversal of 380231821 is 128132083.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 128132083 = 31 ⋅4133293.

It can be written as a sum of positive squares in 2 ways, for example, as 182520100 + 197711721 = 13510^2 + 14061^2 .

It is a cyclic number.

It is not a de Polignac number, because 380231821 - 2⁷ = 380231693 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 380231821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (380231801) 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, 150966 + ... + 153463.

It is an arithmetic number, because the mean of its divisors is an integer number (95134375).

Almost surely, 2^380231821 is an apocalyptic number.

It is an amenable number.

380231821 is a deficient number, since it is larger than the sum of its proper divisors (305679).

380231821 is a wasteful number, since it uses less digits than its factorization.

380231821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 305678.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 380231821 is about 19499.5338662236. The cubic root of 380231821 is about 724.4629052595.

The spelling of 380231821 in words is "three hundred eighty million, two hundred thirty-one thousand, eight hundred twenty-one".