20729091 has 8 divisors (see below), whose sum is σ = 27687184. Its totient is φ = 13795200.

The previous prime is 20729087. The next prime is 20729099. The reversal of 20729091 is 19092702.

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

It is not a de Polignac number, because 20729091 - 2² = 20729087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20729099) 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 7 ways as a sum of consecutive naturals, for example, 3946 + ... + 7551.

It is an arithmetic number, because the mean of its divisors is an integer number (3460898).

Almost surely, 2^20729091 is an apocalyptic number.

20729091 is a deficient number, since it is larger than the sum of its proper divisors (6958093).

20729091 is a wasteful number, since it uses less digits than its factorization.

20729091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12101.

The product of its (nonzero) digits is 2268, while the sum is 30.

The square root of 20729091 is about 4552.9211502068. The cubic root of 20729091 is about 274.7009023592.

The spelling of 20729091 in words is "twenty million, seven hundred twenty-nine thousand, ninety-one".