213912681 has 4 divisors (see below), whose sum is σ = 285216912. Its totient is φ = 142608452.

The previous prime is 213912653. The next prime is 213912689. The reversal of 213912681 is 186219312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 213912681 - 2¹⁸ = 213650537 is a prime.

It is a super-2 number, since 2×213912681² = 91517270185215522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (213912689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35652111 + ... + 35652116.

It is an arithmetic number, because the mean of its divisors is an integer number (71304228).

Almost surely, 2^213912681 is an apocalyptic number.

It is an amenable number.

213912681 is a deficient number, since it is larger than the sum of its proper divisors (71304231).

213912681 is an equidigital number, since it uses as much as digits as its factorization.

213912681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71304230.

The product of its digits is 5184, while the sum is 33.

The square root of 213912681 is about 14625.7540318440. The cubic root of 213912681 is about 598.0610380160.

The spelling of 213912681 in words is "two hundred thirteen million, nine hundred twelve thousand, six hundred eighty-one".