20738917 has 2 divisors, whose sum is σ = 20738918. Its totient is φ = 20738916.

The previous prime is 20738903. The next prime is 20738933. The reversal of 20738917 is 71983702.

It is a Cunningham number, because it is equal to 4554²+1.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20738916 + 1 = 4554^2 + 1^2 .

It is a cyclic number.

It is not a de Polignac number, because 20738917 - 2²³ = 12350309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20738957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10369458 + 10369459.

It is an arithmetic number, because the mean of its divisors is an integer number (10369459).

Almost surely, 2^20738917 is an apocalyptic number.

It is an amenable number.

20738917 is a deficient number, since it is larger than the sum of its proper divisors (1).

20738917 is an equidigital number, since it uses as much as digits as its factorization.

20738917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 20738917 is about 4554.0001097936. Note that the first 3 decimals coincide. The cubic root of 20738917 is about 274.7443000603.

The spelling of 20738917 in words is "twenty million, seven hundred thirty-eight thousand, nine hundred seventeen".