20378231 has 4 divisors (see below), whose sum is σ = 20929032. Its totient is φ = 19827432.

The previous prime is 20378221. The next prime is 20378233. The reversal of 20378231 is 13287302.

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 20378231 - 2⁶ = 20378167 is a prime.

It is a super-2 number, since 2×20378231² = 830544597378722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20378231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20378233) 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, 275345 + ... + 275418.

It is an arithmetic number, because the mean of its divisors is an integer number (5232258).

Almost surely, 2^20378231 is an apocalyptic number.

20378231 is a deficient number, since it is larger than the sum of its proper divisors (550801).

20378231 is an equidigital number, since it uses as much as digits as its factorization.

20378231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 550800.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 20378231 is about 4514.2254042083. The cubic root of 20378231 is about 273.1422150338.

The spelling of 20378231 in words is "twenty million, three hundred seventy-eight thousand, two hundred thirty-one".