20878259 has 4 divisors (see below), whose sum is σ = 20895816. Its totient is φ = 20860704.

The previous prime is 20878241. The next prime is 20878267. The reversal of 20878259 is 95287802.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20878259 - 2¹² = 20874163 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20875259) 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, 6854 + ... + 9419.

It is an arithmetic number, because the mean of its divisors is an integer number (5223954).

Almost surely, 2^20878259 is an apocalyptic number.

20878259 is a deficient number, since it is larger than the sum of its proper divisors (17557).

20878259 is a wasteful number, since it uses less digits than its factorization.

20878259 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17556.

The product of its (nonzero) digits is 80640, while the sum is 41.

The square root of 20878259 is about 4569.2733557974. The cubic root of 20878259 is about 275.3582504495.

The spelling of 20878259 in words is "twenty million, eight hundred seventy-eight thousand, two hundred fifty-nine".