820353901 has 4 divisors (see below), whose sum is σ = 824518332. Its totient is φ = 816189472.

The previous prime is 820353889. The next prime is 820353917. The reversal of 820353901 is 109353028.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 609349225 + 211004676 = 24685^2 + 14526^2 .

It is a cyclic number.

It is not a de Polignac number, because 820353901 - 2¹⁷ = 820222829 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820353971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2081920 + ... + 2082313.

It is an arithmetic number, because the mean of its divisors is an integer number (206129583).

Almost surely, 2^820353901 is an apocalyptic number.

It is an amenable number.

820353901 is a deficient number, since it is larger than the sum of its proper divisors (4164431).

820353901 is a wasteful number, since it uses less digits than its factorization.

820353901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4164430.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 820353901 is about 28641.8208394648. The cubic root of 820353901 is about 936.1247965466.

The spelling of 820353901 in words is "eight hundred twenty million, three hundred fifty-three thousand, nine hundred one".