20416513 has 4 divisors (see below), whose sum is σ = 21987028. Its totient is φ = 18846000.

The previous prime is 20416457. The next prime is 20416549. The reversal of 20416513 is 31561402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31561402 = 2 ⋅15780701.

It can be written as a sum of positive squares in 2 ways, for example, as 6822544 + 13593969 = 2612^2 + 3687^2 .

It is a cyclic number.

It is not a de Polignac number, because 20416513 - 2²¹ = 18319361 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20416213) 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, 785238 + ... + 785263.

It is an arithmetic number, because the mean of its divisors is an integer number (5496757).

Almost surely, 2^20416513 is an apocalyptic number.

It is an amenable number.

20416513 is a deficient number, since it is larger than the sum of its proper divisors (1570515).

20416513 is a wasteful number, since it uses less digits than its factorization.

20416513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1570514.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 20416513 is about 4518.4635663022. The cubic root of 20416513 is about 273.3131472633.

Adding to 20416513 its reverse (31561402), we get a palindrome (51977915).

The spelling of 20416513 in words is "twenty million, four hundred sixteen thousand, five hundred thirteen".