20278 has 4 divisors (see below), whose sum is σ = 30420. Its totient is φ = 10138.

The previous prime is 20269. The next prime is 20287. The reversal of 20278 is 87202.

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

It is an interprime number because it is at equal distance from previous prime (20269) and next prime (20287).

It is a super-2 number, since 2×20278² = 822394568, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5068 + ... + 5071.

It is an arithmetic number, because the mean of its divisors is an integer number (7605).

2²⁰²⁷⁸ is an apocalyptic number.

20278 is a deficient number, since it is larger than the sum of its proper divisors (10142).

20278 is a wasteful number, since it uses less digits than its factorization.

20278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10141.

The product of its (nonzero) digits is 224, while the sum is 19.

The square root of 20278 is about 142.4008426941. The cubic root of 20278 is about 27.2693659157.

Adding to 20278 its product of nonzero digits (224), we get a palindrome (20502).

The spelling of 20278 in words is "twenty thousand, two hundred seventy-eight".