211201681 has 12 divisors (see below), whose sum is σ = 219161712. Its totient is φ = 203419944.

The previous prime is 211201657. The next prime is 211201721. The reversal of 211201681 is 186102112.

211201681 = T₃₀₃ + T₃₀₄ + ... + T₁₀₈₉.

211201681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 211201681 - 2⁵ = 211201649 is a prime.

It is a super-2 number, since 2×211201681² = 89212300114451522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (211201981) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 267970 + ... + 268756.

It is an arithmetic number, because the mean of its divisors is an integer number (18263476).

Almost surely, 2^211201681 is an apocalyptic number.

It is an amenable number.

211201681 is a deficient number, since it is larger than the sum of its proper divisors (7960031).

211201681 is an frugal number, since it uses more digits than its factorization.

211201681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 988 (or 909 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 22.

The square root of 211201681 is about 14532.7795345557. The cubic root of 211201681 is about 595.5238011534.

Adding to 211201681 its reverse (186102112), we get a palindrome (397303793).

It can be divided in two parts, 21120 and 1681, that added together give a square (22801 = 151²).

The spelling of 211201681 in words is "two hundred eleven million, two hundred one thousand, six hundred eighty-one".