20015251 has 2 divisors, whose sum is σ = 20015252. Its totient is φ = 20015250.

The previous prime is 20015231. The next prime is 20015293. The reversal of 20015251 is 15251002.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20015251 - 2¹⁵ = 19982483 is a prime.

It is a super-2 number, since 2×20015251² = 801220545186002, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20015231) by changing a digit.

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 as a sum of consecutive naturals, namely, 10007625 + 10007626.

It is an arithmetic number, because the mean of its divisors is an integer number (10007626).

Almost surely, 2^20015251 is an apocalyptic number.

20015251 is a deficient number, since it is larger than the sum of its proper divisors (1).

20015251 is an equidigital number, since it uses as much as digits as its factorization.

20015251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 20015251 is about 4473.8407437011. The cubic root of 20015251 is about 271.5107401011.

Adding to 20015251 its reverse (15251002), we get a palindrome (35266253).

It can be divided in two parts, 200 and 15251, that added together give a palindrome (15451).

The spelling of 20015251 in words is "twenty million, fifteen thousand, two hundred fifty-one".