821230057 has 4 divisors (see below), whose sum is σ = 821316496. Its totient is φ = 821143620.

The previous prime is 821230049. The next prime is 821230063. The reversal of 821230057 is 750032128.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 821230057 - 2³ = 821230049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (821230037) 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, 26919 + ... + 48652.

It is an arithmetic number, because the mean of its divisors is an integer number (205329124).

Almost surely, 2^821230057 is an apocalyptic number.

It is an amenable number.

821230057 is a deficient number, since it is larger than the sum of its proper divisors (86439).

821230057 is a wasteful number, since it uses less digits than its factorization.

821230057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86438.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 821230057 is about 28657.1118049255. Note that the first 3 decimals coincide. The cubic root of 821230057 is about 936.4579452585.

The spelling of 821230057 in words is "eight hundred twenty-one million, two hundred thirty thousand, fifty-seven".