20315207 has 4 divisors (see below), whose sum is σ = 22162056. Its totient is φ = 18468360.

The previous prime is 20315203. The next prime is 20315219. The reversal of 20315207 is 70251302.

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 20315207 - 2² = 20315203 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 (20315201) 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, 923408 + ... + 923429.

It is an arithmetic number, because the mean of its divisors is an integer number (5540514).

Almost surely, 2^20315207 is an apocalyptic number.

20315207 is a deficient number, since it is larger than the sum of its proper divisors (1846849).

20315207 is a wasteful number, since it uses less digits than its factorization.

20315207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1846848.

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 20315207 is about 4507.2393990113. The cubic root of 20315207 is about 272.8603408445.

Adding to 20315207 its reverse (70251302), we get a palindrome (90566509).

The spelling of 20315207 in words is "twenty million, three hundred fifteen thousand, two hundred seven".