2121227406 has 64 divisors (see below), whose sum is σ = 4852776960. Its totient is φ = 686478240.

The previous prime is 2121227401. The next prime is 2121227419. The reversal of 2121227406 is 6047221212.

2121227406 is a `hidden beast` number, since 21 + 212 + 27 + 406 = 666.

It is a super-3 number, since 3×2121227406³ (a number of 29 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 2121227406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121227401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 319036 + ... + 325616.

It is an arithmetic number, because the mean of its divisors is an integer number (75824640).

Almost surely, 2^2121227406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2121227406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2426388480).

2121227406 is an abundant number, since it is smaller than the sum of its proper divisors (2731549554).

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

2121227406 is a wasteful number, since it uses less digits than its factorization.

2121227406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6766 (or 6760 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 2121227406 is about 46056.7845816444. The cubic root of 2121227406 is about 1284.8795288453.

Adding to 2121227406 its reverse (6047221212), we get a palindrome (8168448618).

The spelling of 2121227406 in words is "two billion, one hundred twenty-one million, two hundred twenty-seven thousand, four hundred six".