213934681 has 4 divisors (see below), whose sum is σ = 226519092. Its totient is φ = 201350272.

The previous prime is 213934673. The next prime is 213934697. The reversal of 213934681 is 186439312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 114832656 + 99102025 = 10716^2 + 9955^2 .

It is a cyclic number.

It is not a de Polignac number, because 213934681 - 2³ = 213934673 is a prime.

It is a super-2 number, since 2×213934681² = 91536095469143522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 213934681.

It is not an unprimeable number, because it can be changed into a prime (213934601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6292180 + ... + 6292213.

It is an arithmetic number, because the mean of its divisors is an integer number (56629773).

Almost surely, 2^213934681 is an apocalyptic number.

It is an amenable number.

213934681 is a deficient number, since it is larger than the sum of its proper divisors (12584411).

213934681 is a wasteful number, since it uses less digits than its factorization.

213934681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12584410.

The product of its digits is 31104, while the sum is 37.

The square root of 213934681 is about 14626.5061104831. The cubic root of 213934681 is about 598.0815399824.

The spelling of 213934681 in words is "two hundred thirteen million, nine hundred thirty-four thousand, six hundred eighty-one".