211225770 has 144 divisors (see below), whose sum is σ = 644705568. Its totient is φ = 47839680.

The previous prime is 211225769. The next prime is 211225771. The reversal of 211225770 is 77522112.

It is an interprime number because it is at equal distance from previous prime (211225769) and next prime (211225771).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211225771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 930397 + ... + 930623.

It is an arithmetic number, because the mean of its divisors is an integer number (4477122).

Almost surely, 2^211225770 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211225770, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322352784).

211225770 is an abundant number, since it is smaller than the sum of its proper divisors (433479798).

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

211225770 is a wasteful number, since it uses less digits than its factorization.

211225770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 465 (or 455 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 27.

The square root of 211225770 is about 14533.6082925060. The cubic root of 211225770 is about 595.5464414838.

Adding to 211225770 its reverse (77522112), we get a palindrome (288747882).

The spelling of 211225770 in words is "two hundred eleven million, two hundred twenty-five thousand, seven hundred seventy".