820997568 has 42 divisors (see below), whose sum is σ = 2353242944. Its totient is φ = 273665664.

The previous prime is 820997563. The next prime is 820997587. The reversal of 820997568 is 865799028.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820997563) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 712096 + ... + 713247.

Almost surely, 2^820997568 is an apocalyptic number.

It is an amenable number.

820997568 is an abundant number, since it is smaller than the sum of its proper divisors (1532245376).

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

820997568 is a wasteful number, since it uses less digits than its factorization.

820997568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1425361 (or 1425348 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 54.

The square root of 820997568 is about 28653.0551250648. The cubic root of 820997568 is about 936.3695669704.

The spelling of 820997568 in words is "eight hundred twenty million, nine hundred ninety-seven thousand, five hundred sixty-eight".