80331821 has 4 divisors (see below), whose sum is σ = 80418492. Its totient is φ = 80245152.

The previous prime is 80331809. The next prime is 80331841. The reversal of 80331821 is 12813308.

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 33477796 + 46854025 = 5786^2 + 6845^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80331821 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 (80331841) 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, 41930 + ... + 43803.

It is an arithmetic number, because the mean of its divisors is an integer number (20104623).

Almost surely, 2^80331821 is an apocalyptic number.

It is an amenable number.

80331821 is a deficient number, since it is larger than the sum of its proper divisors (86671).

80331821 is an equidigital number, since it uses as much as digits as its factorization.

80331821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86670.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 80331821 is about 8962.8020730127. The cubic root of 80331821 is about 431.4818551324.

The spelling of 80331821 in words is "eighty million, three hundred thirty-one thousand, eight hundred twenty-one".