20251613 has 2 divisors, whose sum is σ = 20251614. Its totient is φ = 20251612.

The previous prime is 20251601. The next prime is 20251619. The reversal of 20251613 is 31615202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13271449 + 6980164 = 3643^2 + 2642^2 .

It is a cyclic number.

It is not a de Polignac number, because 20251613 - 2⁴ = 20251597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20251619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10125806 + 10125807.

It is an arithmetic number, because the mean of its divisors is an integer number (10125807).

Almost surely, 2^20251613 is an apocalyptic number.

It is an amenable number.

20251613 is a deficient number, since it is larger than the sum of its proper divisors (1).

20251613 is an equidigital number, since it uses as much as digits as its factorization.

20251613 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 20251613 is about 4500.1792186534. The cubic root of 20251613 is about 272.5753258080.

Adding to 20251613 its reverse (31615202), we get a palindrome (51866815).

It can be divided in two parts, 202 and 51613, that added together give a palindrome (51815).

The spelling of 20251613 in words is "twenty million, two hundred fifty-one thousand, six hundred thirteen".