20726437 has 2 divisors, whose sum is σ = 20726438. Its totient is φ = 20726436.

The previous prime is 20726399. The next prime is 20726441. The reversal of 20726437 is 73462702.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12397441 + 8328996 = 3521^2 + 2886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20726437 is a prime.

It is a Chen prime.

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 20726399 and 20726408.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20726477) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10363218 + 10363219.

It is an arithmetic number, because the mean of its divisors is an integer number (10363219).

Almost surely, 2^20726437 is an apocalyptic number.

It is an amenable number.

20726437 is a deficient number, since it is larger than the sum of its proper divisors (1).

20726437 is an equidigital number, since it uses as much as digits as its factorization.

20726437 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14112, while the sum is 31.

The square root of 20726437 is about 4552.6296796467. The cubic root of 20726437 is about 274.6891782994.

The spelling of 20726437 in words is "twenty million, seven hundred twenty-six thousand, four hundred thirty-seven".