211953406056 has 128 divisors (see below), whose sum is σ = 637615104000. Its totient is φ = 57356335872.

The previous prime is 211953406043. The next prime is 211953406079. The reversal of 211953406056 is 650604359112.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 211953405999 and 211953406017.

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, 20318250 + ... + 20328678.

It is an arithmetic number, because the mean of its divisors is an integer number (4981368000).

Almost surely, 2^211953406056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211953406056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (318807552000).

211953406056 is an abundant number, since it is smaller than the sum of its proper divisors (425661697944).

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

211953406056 is a wasteful number, since it uses less digits than its factorization.

211953406056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16831 (or 16827 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 42.

The spelling of 211953406056 in words is "two hundred eleven billion, nine hundred fifty-three million, four hundred six thousand, fifty-six".