20715005 has 8 divisors (see below), whose sum is σ = 25530072. Its totient is φ = 16123968.

The previous prime is 20714983. The next prime is 20715007. The reversal of 20715005 is 50051702.

It can be written as a sum of positive squares in 4 ways, for example, as 4826809 + 15888196 = 2197^2 + 3986^2 .

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 20715005 - 2²⁴ = 3937789 is a prime.

It is a super-2 number, since 2×20715005² = 858222864300050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20715007) 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, 55802 + ... + 56171.

It is an arithmetic number, because the mean of its divisors is an integer number (3191259).

Almost surely, 2^20715005 is an apocalyptic number.

It is an amenable number.

20715005 is a deficient number, since it is larger than the sum of its proper divisors (4815067).

20715005 is a wasteful number, since it uses less digits than its factorization.

20715005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112015.

The product of its (nonzero) digits is 350, while the sum is 20.

The square root of 20715005 is about 4551.3739683748. The cubic root of 20715005 is about 274.6386659318.

Adding to 20715005 its reverse (50051702), we get a palindrome (70766707).

The spelling of 20715005 in words is "twenty million, seven hundred fifteen thousand, five".