20872213 has 2 divisors, whose sum is σ = 20872214. Its totient is φ = 20872212.

The previous prime is 20872211. The next prime is 20872217. The reversal of 20872213 is 31227802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16305444 + 4566769 = 4038^2 + 2137^2 .

It is a cyclic number.

It is not a de Polignac number, because 20872213 - 2¹ = 20872211 is a prime.

Together with 20872211, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20872211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10436106 + 10436107.

It is an arithmetic number, because the mean of its divisors is an integer number (10436107).

Almost surely, 2^20872213 is an apocalyptic number.

It is an amenable number.

20872213 is a deficient number, since it is larger than the sum of its proper divisors (1).

20872213 is an equidigital number, since it uses as much as digits as its factorization.

20872213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 20872213 is about 4568.6117147335. The cubic root of 20872213 is about 275.3316681451.

The spelling of 20872213 in words is "twenty million, eight hundred seventy-two thousand, two hundred thirteen".