401565381 has 16 divisors (see below), whose sum is σ = 647904384. Its totient is φ = 215967744.

The previous prime is 401565343. The next prime is 401565383. The reversal of 401565381 is 183565104.

It is not a de Polignac number, because 401565381 - 2⁷ = 401565253 is a prime.

It is a super-2 number, since 2×401565381² = 322509510435350322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401565383) 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 15 ways as a sum of consecutive naturals, for example, 562060 + ... + 562773.

It is an arithmetic number, because the mean of its divisors is an integer number (40494024).

Almost surely, 2^401565381 is an apocalyptic number.

It is an amenable number.

401565381 is a deficient number, since it is larger than the sum of its proper divisors (246339003).

401565381 is a wasteful number, since it uses less digits than its factorization.

401565381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1124860.

The product of its (nonzero) digits is 14400, while the sum is 33.

The square root of 401565381 is about 20039.0963119598. The cubic root of 401565381 is about 737.7662007911.

It can be divided in two parts, 4015 and 65381, that added together give a palindrome (69396).

The spelling of 401565381 in words is "four hundred one million, five hundred sixty-five thousand, three hundred eighty-one".