20091001 has 8 divisors (see below), whose sum is σ = 23038400. Its totient is φ = 17162928.

The previous prime is 20090977. The next prime is 20091023. The reversal of 20091001 is 10019002.

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 20091001 - 2⁵ = 20090969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20091101) 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, 2526 + ... + 6823.

It is an arithmetic number, because the mean of its divisors is an integer number (2879800).

Almost surely, 2^20091001 is an apocalyptic number.

It is an amenable number.

20091001 is a deficient number, since it is larger than the sum of its proper divisors (2947399).

20091001 is an equidigital number, since it uses as much as digits as its factorization.

20091001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9663.

The product of its (nonzero) digits is 18, while the sum is 13.

The square root of 20091001 is about 4482.2986290518. The cubic root of 20091001 is about 271.8528300238.

The spelling of 20091001 in words is "twenty million, ninety-one thousand, one".