8213681 has 8 divisors (see below), whose sum is σ = 9881280. Its totient is φ = 6669648.

The previous prime is 8213677. The next prime is 8213693. The reversal of 8213681 is 1863128.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8213681 - 2² = 8213677 is a prime.

It is a super-2 number, since 2×8213681² = 134929111139522, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8213671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30746 + ... + 31011.

It is an arithmetic number, because the mean of its divisors is an integer number (1235160).

Almost surely, 2^8213681 is an apocalyptic number.

It is an amenable number.

8213681 is a deficient number, since it is larger than the sum of its proper divisors (1667599).

8213681 is a wasteful number, since it uses less digits than its factorization.

8213681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61783.

The product of its digits is 2304, while the sum is 29.

The square root of 8213681 is about 2865.9520233249. The cubic root of 8213681 is about 201.7650521310.

The spelling of 8213681 in words is "eight million, two hundred thirteen thousand, six hundred eighty-one".