401320021 has 2 divisors, whose sum is σ = 401320022. Its totient is φ = 401320020.

The previous prime is 401320001. The next prime is 401320043. The reversal of 401320021 is 120023104.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211266225 + 190053796 = 14535^2 + 13786^2 .

It is a cyclic number.

It is not a de Polignac number, because 401320021 - 2⁹ = 401319509 is a prime.

It is a super-2 number, since 2×401320021² = 322115518510880882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 401319983 and 401320010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (401320001) 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 as a sum of consecutive naturals, namely, 200660010 + 200660011.

It is an arithmetic number, because the mean of its divisors is an integer number (200660011).

Almost surely, 2^401320021 is an apocalyptic number.

It is an amenable number.

401320021 is a deficient number, since it is larger than the sum of its proper divisors (1).

401320021 is an equidigital number, since it uses as much as digits as its factorization.

401320021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 401320021 is about 20032.9733439647. The cubic root of 401320021 is about 737.6159096189.

Adding to 401320021 its reverse (120023104), we get a palindrome (521343125).

The spelling of 401320021 in words is "four hundred one million, three hundred twenty thousand, twenty-one".