20660501 has 2 divisors, whose sum is σ = 20660502. Its totient is φ = 20660500.

The previous prime is 20660483. The next prime is 20660527. The reversal of 20660501 is 10506602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15602500 + 5058001 = 3950^2 + 2249^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20660501 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20660701) 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, 10330250 + 10330251.

It is an arithmetic number, because the mean of its divisors is an integer number (10330251).

Almost surely, 2^20660501 is an apocalyptic number.

It is an amenable number.

20660501 is a deficient number, since it is larger than the sum of its proper divisors (1).

20660501 is an equidigital number, since it uses as much as digits as its factorization.

20660501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 20660501 is about 4545.3823821544. The cubic root of 20660501 is about 274.3975837873.

The spelling of 20660501 in words is "twenty million, six hundred sixty thousand, five hundred one".