401221212 has 72 divisors (see below), whose sum is σ = 1092679056. Its totient is φ = 114250752.

The previous prime is 401221207. The next prime is 401221231. The reversal of 401221212 is 212122104.

It is a junction number, because it is equal to n+sod(n) for n = 401221191 and 401221200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 206598 + ... + 208530.

It is an arithmetic number, because the mean of its divisors is an integer number (15176098).

Almost surely, 2^401221212 is an apocalyptic number.

401221212 is a gapful number since it is divisible by the number (42) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 401221212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (546339528).

401221212 is an abundant number, since it is smaller than the sum of its proper divisors (691457844).

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

401221212 is a wasteful number, since it uses less digits than its factorization.

401221212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2307 (or 2298 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 401221212 is about 20030.5070330234. The cubic root of 401221212 is about 737.5553685137. Note that the first 3 decimals are identical.

Adding to 401221212 its reverse (212122104), we get a palindrome (613343316).

The spelling of 401221212 in words is "four hundred one million, two hundred twenty-one thousand, two hundred twelve".