20145342251 has 4 divisors (see below), whose sum is σ = 20636692104. Its totient is φ = 19653992400.

The previous prime is 20145342229. The next prime is 20145342253. The reversal of 20145342251 is 15224354102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15224354102 = 2 ⋅7612177051.

It is a cyclic number.

It is not a de Polignac number, because 20145342251 - 2¹⁴ = 20145325867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20145342253) 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, 245674865 + ... + 245674946.

It is an arithmetic number, because the mean of its divisors is an integer number (5159173026).

Almost surely, 2^20145342251 is an apocalyptic number.

20145342251 is a deficient number, since it is larger than the sum of its proper divisors (491349853).

20145342251 is an equidigital number, since it uses as much as digits as its factorization.

20145342251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 491349852.

The product of its (nonzero) digits is 9600, while the sum is 29.

Adding to 20145342251 its reverse (15224354102), we get a palindrome (35369696353).

The spelling of 20145342251 in words is "twenty billion, one hundred forty-five million, three hundred forty-two thousand, two hundred fifty-one".