401821620 has 48 divisors (see below), whose sum is σ = 1146337920. Its totient is φ = 105129856.

The previous prime is 401821603. The next prime is 401821621. The reversal of 401821620 is 26128104.

It is a super-2 number, since 2×401821620² = 322921228598848800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401821621) 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, 60000 + ... + 66359.

It is an arithmetic number, because the mean of its divisors is an integer number (23882040).

Almost surely, 2^401821620 is an apocalyptic number.

It is an amenable number.

401821620 is an abundant number, since it is smaller than the sum of its proper divisors (744516300).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

401821620 is a wasteful number, since it uses less digits than its factorization.

401821620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126424 (or 126422 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

The square root of 401821620 is about 20045.4887692967. The cubic root of 401821620 is about 737.9230903761.

Adding to 401821620 its reverse (26128104), we get a palindrome (427949724).

The spelling of 401821620 in words is "four hundred one million, eight hundred twenty-one thousand, six hundred twenty".