820999088100 has 81 divisors (see below), whose sum is σ = 2573461236073. Its totient is φ = 218925841440.

The previous prime is 820999088089. The next prime is 820999088177. The reversal of 820999088100 is 1880999028.

It is a happy number.

The square root of 820999088100 is 906090.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 295559671716 + 525439416384 = 543654^2 + 724872^2 .

It is a super-2 number, since 2×820999088100² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 27167599 + ... + 27197801.

Almost surely, 2^820999088100 is an apocalyptic number.

820999088100 is the 906090-th square number.

It is an amenable number.

820999088100 is an abundant number, since it is smaller than the sum of its proper divisors (1752462147973).

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

820999088100 is an equidigital number, since it uses as much as digits as its factorization.

820999088100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60426 (or 30213 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 54.

The spelling of 820999088100 in words is "eight hundred twenty billion, nine hundred ninety-nine million, eighty-eight thousand, one hundred".