29681 has 4 divisors (see below), whose sum is σ = 30192. Its totient is φ = 29172.

The previous prime is 29671. The next prime is 29683. The reversal of 29681 is 18692.

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 29681 - 2¹⁰ = 28657 is a prime.

It is a super-2 number, since 2×29681² = 1761923522, 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 29681.

It is not an unprimeable number, because it can be changed into a prime (29683) 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, 155 + ... + 288.

It is an arithmetic number, because the mean of its divisors is an integer number (7548).

2²⁹⁶⁸¹ is an apocalyptic number.

It is an amenable number.

29681 is a deficient number, since it is larger than the sum of its proper divisors (511).

29681 is an equidigital number, since it uses as much as digits as its factorization.

29681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510.

The product of its digits is 864, while the sum is 26.

The square root of 29681 is about 172.2817459860. The cubic root of 29681 is about 30.9617982428.

The spelling of 29681 in words is "twenty-nine thousand, six hundred eighty-one".