20909001 has 8 divisors (see below), whose sum is σ = 29090880. Its totient is φ = 13333232.

The previous prime is 20908981. The next prime is 20909023. The reversal of 20909001 is 10090902.

It is a happy number.

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 20909001 - 2¹⁴ = 20892617 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20909081) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151446 + ... + 151583.

It is an arithmetic number, because the mean of its divisors is an integer number (3636360).

Almost surely, 2^20909001 is an apocalyptic number.

It is an amenable number.

20909001 is a deficient number, since it is larger than the sum of its proper divisors (8181879).

20909001 is a wasteful number, since it uses less digits than its factorization.

20909001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303055.

The product of its (nonzero) digits is 162, while the sum is 21.

The square root of 20909001 is about 4572.6361106040. The cubic root of 20909001 is about 275.4933337430.

Adding to 20909001 its reverse (10090902), we get a palindrome (30999903).

The spelling of 20909001 in words is "twenty million, nine hundred nine thousand, one".