211504400640 has 864 divisors, whose sum is σ = 860588426880. Its totient is φ = 49304567808.

The previous prime is 211504400629. The next prime is 211504400689. The reversal of 211504400640 is 46004405112.

211504400640 is a `hidden beast` number, since 2 + 1 + 15 + 0 + 4 + 4 + 0 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

It is a super-2 number, since 2×211504400640² (a number of 23 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 76825504 + ... + 76828256.

It is an arithmetic number, because the mean of its divisors is an integer number (996051420).

Almost surely, 2^211504400640 is an apocalyptic number.

211504400640 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 211504400640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (430294213440).

211504400640 is an abundant number, since it is smaller than the sum of its proper divisors (649084026240).

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

211504400640 is a wasteful number, since it uses less digits than its factorization.

211504400640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2821 (or 2795 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

Adding to 211504400640 its reverse (46004405112), we get a palindrome (257508805752).

The spelling of 211504400640 in words is "two hundred eleven billion, five hundred four million, four hundred thousand, six hundred forty".