211161564 has 18 divisors (see below), whose sum is σ = 533769600. Its totient is φ = 70387176.

The previous prime is 211161523. The next prime is 211161569. The reversal of 211161564 is 465161112.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×211161564² = 89178412221852192, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211161569) 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 in 5 ways as a sum of consecutive naturals, for example, 2932764 + ... + 2932835.

Almost surely, 2^211161564 is an apocalyptic number.

It is an amenable number.

211161564 is an abundant number, since it is smaller than the sum of its proper divisors (322608036).

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

211161564 is a wasteful number, since it uses less digits than its factorization.

211161564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5865609 (or 5865604 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 211161564 is about 14531.3992443949. The cubic root of 211161564 is about 595.4860928975.

The spelling of 211161564 in words is "two hundred eleven million, one hundred sixty-one thousand, five hundred sixty-four".