401544221 has 4 divisors (see below), whose sum is σ = 432432252. Its totient is φ = 370656192.

The previous prime is 401544197. The next prime is 401544287. The reversal of 401544221 is 122445104.

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

It can be written as a sum of positive squares in 2 ways, for example, as 137124100 + 264420121 = 11710^2 + 16261^2 .

It is a cyclic number.

It is not a de Polignac number, because 401544221 - 2²² = 397349917 is a prime.

It is a super-2 number, since 2×401544221² = 322475522836993682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401544721) 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, 15443996 + ... + 15444021.

It is an arithmetic number, because the mean of its divisors is an integer number (108108063).

Almost surely, 2^401544221 is an apocalyptic number.

It is an amenable number.

401544221 is a deficient number, since it is larger than the sum of its proper divisors (30888031).

401544221 is a wasteful number, since it uses less digits than its factorization.

401544221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30888030.

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 401544221 is about 20038.5683370844. The cubic root of 401544221 is about 737.7532419988.

Adding to 401544221 its reverse (122445104), we get a palindrome (523989325).

The spelling of 401544221 in words is "four hundred one million, five hundred forty-four thousand, two hundred twenty-one".