20513145 has 8 divisors (see below), whose sum is σ = 32821056. Its totient is φ = 10940336.

The previous prime is 20513113. The next prime is 20513177. The reversal of 20513145 is 54131502.

It is an interprime number because it is at equal distance from previous prime (20513113) and next prime (20513177).

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 20513145 - 2⁵ = 20513113 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 683757 + ... + 683786.

It is an arithmetic number, because the mean of its divisors is an integer number (4102632).

Almost surely, 2^20513145 is an apocalyptic number.

It is an amenable number.

20513145 is a deficient number, since it is larger than the sum of its proper divisors (12307911).

20513145 is a wasteful number, since it uses less digits than its factorization.

20513145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1367551.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 20513145 is about 4529.1439588514. The cubic root of 20513145 is about 273.7436686678.

Adding to 20513145 its reverse (54131502), we get a palindrome (74644647).

The spelling of 20513145 in words is "twenty million, five hundred thirteen thousand, one hundred forty-five".