211009986 has 48 divisors (see below), whose sum is σ = 500329440. Its totient is φ = 63740160.

The previous prime is 211009973. The next prime is 211009999. The reversal of 211009986 is 689900112.

It is an interprime number because it is at equal distance from previous prime (211009973) and next prime (211009999).

It is a self number, because there is not a number n which added to its sum of digits gives 211009986.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 68385 + ... + 71403.

It is an arithmetic number, because the mean of its divisors is an integer number (10423530).

Almost surely, 2^211009986 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 211009986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (250164720).

211009986 is an abundant number, since it is smaller than the sum of its proper divisors (289319454).

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

211009986 is a wasteful number, since it uses less digits than its factorization.

211009986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3391 (or 3388 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 211009986 is about 14526.1827745626. The cubic root of 211009986 is about 595.3435729622.

The spelling of 211009986 in words is "two hundred eleven million, nine thousand, nine hundred eighty-six".