20390513 has 8 divisors (see below), whose sum is σ = 23955456. Its totient is φ = 17110800.

The previous prime is 20390483. The next prime is 20390549. The reversal of 20390513 is 31509302.

It is a happy number.

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 20390513 - 2¹⁴ = 20374129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20390113) 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, 71153 + ... + 71438.

It is an arithmetic number, because the mean of its divisors is an integer number (2994432).

Almost surely, 2^20390513 is an apocalyptic number.

It is an amenable number.

20390513 is a deficient number, since it is larger than the sum of its proper divisors (3564943).

20390513 is a wasteful number, since it uses less digits than its factorization.

20390513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142615.

The product of its (nonzero) digits is 810, while the sum is 23.

The square root of 20390513 is about 4515.5855655718. The cubic root of 20390513 is about 273.1970784636.

Adding to 20390513 its reverse (31509302), we get a palindrome (51899815).

The spelling of 20390513 in words is "twenty million, three hundred ninety thousand, five hundred thirteen".