820641201 has 4 divisors (see below), whose sum is σ = 1094188272. Its totient is φ = 547094132.

The previous prime is 820641163. The next prime is 820641209. The reversal of 820641201 is 102146028.

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.

It is a cyclic number.

It is not a de Polignac number, because 820641201 - 2⁶ = 820641137 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (820641209) 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, 136773531 + ... + 136773536.

It is an arithmetic number, because the mean of its divisors is an integer number (273547068).

Almost surely, 2^820641201 is an apocalyptic number.

It is an amenable number.

820641201 is a deficient number, since it is larger than the sum of its proper divisors (273547071).

820641201 is a wasteful number, since it uses less digits than its factorization.

820641201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273547070.

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 820641201 is about 28646.8357938534. The cubic root of 820641201 is about 936.2340653484.

Adding to 820641201 its reverse (102146028), we get a palindrome (922787229).

The spelling of 820641201 in words is "eight hundred twenty million, six hundred forty-one thousand, two hundred one".