211421023440 has 320 divisors, whose sum is σ = 720313896960. Its totient is φ = 50873518080.

The previous prime is 211421023343. The next prime is 211421023459. The reversal of 211421023440 is 44320124112.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 211421023440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 328803759 + ... + 328804401.

It is an arithmetic number, because the mean of its divisors is an integer number (2250980928).

Almost surely, 2^211421023440 is an apocalyptic number.

211421023440 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 211421023440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (360156948480).

211421023440 is an abundant number, since it is smaller than the sum of its proper divisors (508892873520).

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

211421023440 is a wasteful number, since it uses less digits than its factorization.

211421023440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1402 (or 1396 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 211421023440 its reverse (44320124112), we get a palindrome (255741147552).

The spelling of 211421023440 in words is "two hundred eleven billion, four hundred twenty-one million, twenty-three thousand, four hundred forty".