211213440 has 256 divisors, whose sum is σ = 793152000. Its totient is φ = 52936704.

The previous prime is 211213421. The next prime is 211213469. The reversal of 211213440 is 44312112.

211213440 is a `hidden beast` number, since 2 + 11 + 213 + 440 = 666.

It is a super-2 number, since 2×211213440² = 89222234473267200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 293401 + ... + 294119.

It is an arithmetic number, because the mean of its divisors is an integer number (3098250).

Almost surely, 2^211213440 is an apocalyptic number.

211213440 is a gapful number since it is divisible by the number (20) 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 211213440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (396576000).

211213440 is an abundant number, since it is smaller than the sum of its proper divisors (581938560).

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

211213440 is a wasteful number, since it uses less digits than its factorization.

211213440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 764 (or 746 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 211213440 is about 14533.1840970931. The cubic root of 211213440 is about 595.5348532031.

Adding to 211213440 its reverse (44312112), we get a palindrome (255525552).

The spelling of 211213440 in words is "two hundred eleven million, two hundred thirteen thousand, four hundred forty".