820851400 has 48 divisors (see below), whose sum is σ = 1910452500. Its totient is φ = 328001280.

The previous prime is 820851397. The next prime is 820851461. The reversal of 820851400 is 4158028.

It can be written as a sum of positive squares in 6 ways, for example, as 290838916 + 530012484 = 17054^2 + 23022^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 297226 + ... + 299974.

Almost surely, 2^820851400 is an apocalyptic number.

It is an amenable number.

820851400 is an abundant number, since it is smaller than the sum of its proper divisors (1089601100).

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

820851400 is a wasteful number, since it uses less digits than its factorization.

820851400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4258 (or 4249 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 820851400 is about 28650.5043585623. The cubic root of 820851400 is about 936.3139941748.

The spelling of 820851400 in words is "eight hundred twenty million, eight hundred fifty-one thousand, four hundred".