821164100 has 18 divisors (see below), whose sum is σ = 1781926314. Its totient is φ = 328465600.

The previous prime is 821164067. The next prime is 821164121. The reversal of 821164100 is 1461128.

It can be written as a sum of positive squares in 3 ways, for example, as 247369984 + 573794116 = 15728^2 + 23954^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4105721 + ... + 4105920.

Almost surely, 2^821164100 is an apocalyptic number.

It is an amenable number.

821164100 is an abundant number, since it is smaller than the sum of its proper divisors (960762214).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

821164100 is a wasteful number, since it uses less digits than its factorization.

821164100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8211655 (or 8211648 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 821164100 is about 28655.9609854564. The cubic root of 821164100 is about 936.4328740823.

The spelling of 821164100 in words is "eight hundred twenty-one million, one hundred sixty-four thousand, one hundred".