20667001 has 4 divisors (see below), whose sum is σ = 20744100. Its totient is φ = 20589904.

The previous prime is 20666999. The next prime is 20667011. The reversal of 20667001 is 10076602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12257001 + 8410000 = 3501^2 + 2900^2 .

It is a cyclic number.

It is not a de Polignac number, because 20667001 - 2¹ = 20666999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20667011) 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, 38146 + ... + 38683.

It is an arithmetic number, because the mean of its divisors is an integer number (5186025).

Almost surely, 2^20667001 is an apocalyptic number.

It is an amenable number.

20667001 is a deficient number, since it is larger than the sum of its proper divisors (77099).

20667001 is an equidigital number, since it uses as much as digits as its factorization.

20667001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77098.

The product of its (nonzero) digits is 504, while the sum is 22.

The square root of 20667001 is about 4546.0973372773. The cubic root of 20667001 is about 274.4263568438.

The spelling of 20667001 in words is "twenty million, six hundred sixty-seven thousand, one".