20507207 has 4 divisors (see below), whose sum is σ = 23436816. Its totient is φ = 17577600.

The previous prime is 20507203. The next prime is 20507231. The reversal of 20507207 is 70270502.

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

It is a cyclic number.

It is not a de Polignac number, because 20507207 - 2² = 20507203 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20507203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1464794 + ... + 1464807.

It is an arithmetic number, because the mean of its divisors is an integer number (5859204).

Almost surely, 2^20507207 is an apocalyptic number.

20507207 is a deficient number, since it is larger than the sum of its proper divisors (2929609).

20507207 is an equidigital number, since it uses as much as digits as its factorization.

20507207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2929608.

The product of its (nonzero) digits is 980, while the sum is 23.

The square root of 20507207 is about 4528.4883791393. The cubic root of 20507207 is about 273.7172523256.

Adding to 20507207 its reverse (70270502), we get a palindrome (90777709).

The spelling of 20507207 in words is "twenty million, five hundred seven thousand, two hundred seven".