20118513 has 8 divisors (see below), whose sum is σ = 26964448. Its totient is φ = 13342464.

The previous prime is 20118509. The next prime is 20118517. The reversal of 20118513 is 31581102.

It is an interprime number because it is at equal distance from previous prime (20118509) and next prime (20118517).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20118513 - 2² = 20118509 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20118513.

It is not an unprimeable number, because it can be changed into a prime (20118517) 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, 16795 + ... + 17952.

It is an arithmetic number, because the mean of its divisors is an integer number (3370556).

Almost surely, 2^20118513 is an apocalyptic number.

It is an amenable number.

20118513 is a deficient number, since it is larger than the sum of its proper divisors (6845935).

20118513 is a wasteful number, since it uses less digits than its factorization.

20118513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34943.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 20118513 is about 4485.3665402061. The cubic root of 20118513 is about 271.9768623989.

Adding to 20118513 its reverse (31581102), we get a palindrome (51699615).

The spelling of 20118513 in words is "twenty million, one hundred eighteen thousand, five hundred thirteen".