20517107 has 6 divisors (see below), whose sum is σ = 22216932. Its totient is φ = 18938712.

The previous prime is 20517067. The next prime is 20517109. The reversal of 20517107 is 70171502.

It is a happy number.

It is not a de Polignac number, because 20517107 - 2¹² = 20513011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20517109) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 60533 + ... + 60870.

It is an arithmetic number, because the mean of its divisors is an integer number (3702822).

Almost surely, 2^20517107 is an apocalyptic number.

20517107 is a deficient number, since it is larger than the sum of its proper divisors (1699825).

20517107 is a wasteful number, since it uses less digits than its factorization.

20517107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121429 (or 121416 counting only the distinct ones).

The product of its (nonzero) digits is 490, while the sum is 23.

The square root of 20517107 is about 4529.5813272310. The cubic root of 20517107 is about 273.7612915562.

Adding to 20517107 its reverse (70171502), we get a palindrome (90688609).

The spelling of 20517107 in words is "twenty million, five hundred seventeen thousand, one hundred seven".