211307986 has 4 divisors (see below), whose sum is σ = 316961982. Its totient is φ = 105653992.

The previous prime is 211307981. The next prime is 211307989. The reversal of 211307986 is 689703112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 120582361 + 90725625 = 10981^2 + 9525^2 .

It is not an unprimeable number, because it can be changed into a prime (211307981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52826995 + ... + 52826998.

Almost surely, 2^211307986 is an apocalyptic number.

211307986 is a deficient number, since it is larger than the sum of its proper divisors (105653996).

211307986 is a wasteful number, since it uses less digits than its factorization.

211307986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105653995.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 211307986 is about 14536.4364959229. The cubic root of 211307986 is about 595.6237001991.

The spelling of 211307986 in words is "two hundred eleven million, three hundred seven thousand, nine hundred eighty-six".