401664331 has 4 divisors (see below), whose sum is σ = 411461064. Its totient is φ = 391867600.

The previous prime is 401664283. The next prime is 401664343. The reversal of 401664331 is 133466104.

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

It is a cyclic number.

It is not a de Polignac number, because 401664331 - 2¹⁵ = 401631563 is a prime.

It is a super-2 number, since 2×401664331² = 322668469595355122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 401664331.

It is not an unprimeable number, because it can be changed into a prime (401694331) 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, 4898305 + ... + 4898386.

It is an arithmetic number, because the mean of its divisors is an integer number (102865266).

Almost surely, 2^401664331 is an apocalyptic number.

401664331 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

401664331 is a deficient number, since it is larger than the sum of its proper divisors (9796733).

401664331 is an equidigital number, since it uses as much as digits as its factorization.

401664331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9796732.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 401664331 is about 20041.5650835956. The cubic root of 401664331 is about 737.8267936390.

The spelling of 401664331 in words is "four hundred one million, six hundred sixty-four thousand, three hundred thirty-one".