29920865 has 16 divisors (see below), whose sum is σ = 38782800. Its totient is φ = 22029312.

The previous prime is 29920853. The next prime is 29920871. The reversal of 29920865 is 56802992.

It can be written as a sum of positive squares in 8 ways, for example, as 1607824 + 28313041 = 1268^2 + 5321^2 .

It is a cyclic number.

It is not a de Polignac number, because 29920865 - 2²⁰ = 28872289 is a prime.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 36581 + ... + 37389.

It is an arithmetic number, because the mean of its divisors is an integer number (2423925).

Almost surely, 2^29920865 is an apocalyptic number.

It is an amenable number.

29920865 is a deficient number, since it is larger than the sum of its proper divisors (8861935).

29920865 is a wasteful number, since it uses less digits than its factorization.

29920865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1396.

The product of its (nonzero) digits is 77760, while the sum is 41.

The square root of 29920865 is about 5469.9968007303. The cubic root of 29920865 is about 310.4497979641.

The spelling of 29920865 in words is "twenty-nine million, nine hundred twenty thousand, eight hundred sixty-five".