20660687 has 2 divisors, whose sum is σ = 20660688. Its totient is φ = 20660686.

The previous prime is 20660681. The next prime is 20660701. The reversal of 20660687 is 78606602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20660687 - 2¹⁴ = 20644303 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20660681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10330343 + 10330344.

It is an arithmetic number, because the mean of its divisors is an integer number (10330344).

Almost surely, 2^20660687 is an apocalyptic number.

20660687 is a deficient number, since it is larger than the sum of its proper divisors (1).

20660687 is an equidigital number, since it uses as much as digits as its factorization.

20660687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 20660687 is about 4545.4028424332. The cubic root of 20660687 is about 274.3984072233.

The spelling of 20660687 in words is "twenty million, six hundred sixty thousand, six hundred eighty-seven".