401644403 has 4 divisors (see below), whose sum is σ = 415494240. Its totient is φ = 387794568.

The previous prime is 401644391. The next prime is 401644429. The reversal of 401644403 is 304446104.

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 401644403 - 2²⁰ = 400595827 is a prime.

It is a super-2 number, since 2×401644403² = 322636452922452818, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (401644603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6924875 + ... + 6924932.

It is an arithmetic number, because the mean of its divisors is an integer number (103873560).

Almost surely, 2^401644403 is an apocalyptic number.

401644403 is a deficient number, since it is larger than the sum of its proper divisors (13849837).

401644403 is a wasteful number, since it uses less digits than its factorization.

401644403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13849836.

The product of its (nonzero) digits is 4608, while the sum is 26.

The square root of 401644403 is about 20041.0679106678. The cubic root of 401644403 is about 737.8145913643.

The spelling of 401644403 in words is "four hundred one million, six hundred forty-four thousand, four hundred three".