213111405 has 80 divisors (see below), whose sum is σ = 435791664. Its totient is φ = 98703360.

The previous prime is 213111383. The next prime is 213111407. The reversal of 213111405 is 504111312.

It can be written as a sum of positive squares in 8 ways, for example, as 48399849 + 164711556 = 6957^2 + 12834^2 .

It is not a de Polignac number, because 213111405 - 2⁵ = 213111373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213111407) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 88315 + ... + 90695.

Almost surely, 2^213111405 is an apocalyptic number.

It is an amenable number.

213111405 is an abundant number, since it is smaller than the sum of its proper divisors (222680259).

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

213111405 is a wasteful number, since it uses less digits than its factorization.

213111405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2428 (or 2419 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 213111405 is about 14598.3356928110. The cubic root of 213111405 is about 597.3133629244.

Adding to 213111405 its reverse (504111312), we get a palindrome (717222717).

The spelling of 213111405 in words is "two hundred thirteen million, one hundred eleven thousand, four hundred five".