20505001 has 8 divisors (see below), whose sum is σ = 23140800. Its totient is φ = 17997840.

The previous prime is 20504999. The next prime is 20505007. The reversal of 20505001 is 10050502.

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 20505001 - 2¹ = 20504999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20505007) 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, 31821 + ... + 32458.

It is an arithmetic number, because the mean of its divisors is an integer number (2892600).

Almost surely, 2^20505001 is an apocalyptic number.

It is an amenable number.

20505001 is a deficient number, since it is larger than the sum of its proper divisors (2635799).

20505001 is a wasteful number, since it uses less digits than its factorization.

20505001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64319.

The product of its (nonzero) digits is 50, while the sum is 13.

The square root of 20505001 is about 4528.2448034531. The cubic root of 20505001 is about 273.7074372085.

Adding to 20505001 its reverse (10050502), we get a palindrome (30555503).

The spelling of 20505001 in words is "twenty million, five hundred five thousand, one".