211400505 has 12 divisors (see below), whose sum is σ = 366427620. Its totient is φ = 112746912.

The previous prime is 211400489. The next prime is 211400509. The reversal of 211400505 is 505004112.

211400505 is a `hidden beast` number, since 21 + 140 + 0 + 505 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 46457856 + 164942649 = 6816^2 + 12843^2 .

It is not a de Polignac number, because 211400505 - 2⁴ = 211400489 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (211400509) 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, 2348850 + ... + 2348939.

It is an arithmetic number, because the mean of its divisors is an integer number (30535635).

Almost surely, 2^211400505 is an apocalyptic number.

It is an amenable number.

211400505 is a deficient number, since it is larger than the sum of its proper divisors (155027115).

211400505 is a wasteful number, since it uses less digits than its factorization.

211400505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4697800 (or 4697797 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 211400505 is about 14539.6184612940. The cubic root of 211400505 is about 595.7106167255.

Adding to 211400505 its reverse (505004112), we get a palindrome (716404617).

The spelling of 211400505 in words is "two hundred eleven million, four hundred thousand, five hundred five".