20023251 has 8 divisors (see below), whose sum is σ = 27318720.
Its totient is φ = 13038312.
The previous prime is 20023187. The next prime is 20023259. The reversal of 20023251 is 15232002.
It is a sphenic number, since it is the product of 3 distinct primes.
It is not a de Polignac number, because 20023251 - 26 = 20023187 is a prime.
It is a self number, because there is not a number n which added to its sum of digits gives 20023251.
It is not an unprimeable number, because it can be changed into a prime (20023259) 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 in 7 ways as a sum of consecutive naturals, for example, 77481 + ... + 77738.
It is an arithmetic number, because the mean of its divisors is an integer number (3414840).
Almost surely, 220023251 is an apocalyptic number.
20023251 is a deficient number, since it is larger than the sum of its proper divisors (7295469).
20023251 is a wasteful number, since it uses less digits than its factorization.
20023251 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 155265.
The product of its (nonzero) digits is 120, while the sum is 15.
The square root of 20023251 is about 4474.7347407416.
The cubic root of 20023251 is about 271.5469091303.
Adding to 20023251 its reverse (15232002), we get a palindrome (35255253).
It can be divided in two parts, 2002 and 3251, that added together give a triangular number (5253 = T102).
The spelling of 20023251 in words is "twenty million, twenty-three thousand, two hundred fifty-one".