20781214 has 4 divisors (see below), whose sum is σ = 31171824. Its totient is φ = 10390606.

The previous prime is 20781199. The next prime is 20781217. The reversal of 20781214 is 41218702.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20781217) 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 as a sum of consecutive naturals, namely, 5195302 + ... + 5195305.

It is an arithmetic number, because the mean of its divisors is an integer number (7792956).

Almost surely, 2^20781214 is an apocalyptic number.

20781214 is a deficient number, since it is larger than the sum of its proper divisors (10390610).

20781214 is a wasteful number, since it uses less digits than its factorization.

20781214 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10390609.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 20781214 is about 4558.6416836597. The cubic root of 20781214 is about 274.9309534643.

Adding to 20781214 its reverse (41218702), we get a palindrome (61999916).

The spelling of 20781214 in words is "twenty million, seven hundred eighty-one thousand, two hundred fourteen".