20986237 has 2 divisors, whose sum is σ = 20986238. Its totient is φ = 20986236.

The previous prime is 20986181. The next prime is 20986243. The reversal of 20986237 is 73268902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20985561 + 676 = 4581^2 + 26^2 .

It is a cyclic number.

It is not a de Polignac number, because 20986237 - 2¹⁹ = 20461949 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20986196 and 20986205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20986297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10493118 + 10493119.

It is an arithmetic number, because the mean of its divisors is an integer number (10493119).

Almost surely, 2^20986237 is an apocalyptic number.

It is an amenable number.

20986237 is a deficient number, since it is larger than the sum of its proper divisors (1).

20986237 is an equidigital number, since it uses as much as digits as its factorization.

20986237 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 20986237 is about 4581.0737824226. The cubic root of 20986237 is about 275.8321329212.

The spelling of 20986237 in words is "twenty million, nine hundred eighty-six thousand, two hundred thirty-seven".