400020401 has 8 divisors (see below), whose sum is σ = 436646208. Its totient is φ = 363438000.

The previous prime is 400020391. The next prime is 400020407. The reversal of 400020401 is 104020004.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 400020401 - 2¹⁸ = 399758257 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (11).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400020407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10211 + ... + 30071.

It is an arithmetic number, because the mean of its divisors is an integer number (54580776).

Almost surely, 2^400020401 is an apocalyptic number.

400020401 is the 8945-th centered decagonal number.

It is an amenable number.

400020401 is a deficient number, since it is larger than the sum of its proper divisors (36625807).

400020401 is a wasteful number, since it uses less digits than its factorization.

400020401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21703.

The product of its (nonzero) digits is 32, while the sum is 11.

The square root of 400020401 is about 20000.5100184970. The cubic root of 400020401 is about 736.8188258362.

Adding to 400020401 its reverse (104020004), we get a palindrome (504040405).

The spelling of 400020401 in words is "four hundred million, twenty thousand, four hundred one".