211686164 has 6 divisors (see below), whose sum is σ = 370450794. Its totient is φ = 105843080.

The previous prime is 211686151. The next prime is 211686169. The reversal of 211686164 is 461686112.

It can be written as a sum of positive squares in only one way, i.e., 197683600 + 14002564 = 14060^2 + 3742^2 .

It is a super-2 number, since 2×211686164² = 89622064058069792, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211686169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26460767 + ... + 26460774.

It is an arithmetic number, because the mean of its divisors is an integer number (61741799).

Almost surely, 2^211686164 is an apocalyptic number.

It is an amenable number.

211686164 is a deficient number, since it is larger than the sum of its proper divisors (158764630).

211686164 is a wasteful number, since it uses less digits than its factorization.

211686164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52921545 (or 52921543 counting only the distinct ones).

The product of its digits is 13824, while the sum is 35.

The square root of 211686164 is about 14549.4386145995. The cubic root of 211686164 is about 595.9788177689.

The spelling of 211686164 in words is "two hundred eleven million, six hundred eighty-six thousand, one hundred sixty-four".