401843021 has 2 divisors, whose sum is σ = 401843022. Its totient is φ = 401843020.

The previous prime is 401842999. The next prime is 401843033. The reversal of 401843021 is 120348104.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 386554921 + 15288100 = 19661^2 + 3910^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-401843021 is a prime.

It is a super-2 number, since 2×401843021² = 322955627052812882, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (401843081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200921510 + 200921511.

It is an arithmetic number, because the mean of its divisors is an integer number (200921511).

Almost surely, 2^401843021 is an apocalyptic number.

It is an amenable number.

401843021 is a deficient number, since it is larger than the sum of its proper divisors (1).

401843021 is an equidigital number, since it uses as much as digits as its factorization.

401843021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 401843021 is about 20046.0225730692. The cubic root of 401843021 is about 737.9361907262.

The spelling of 401843021 in words is "four hundred one million, eight hundred forty-three thousand, twenty-one".