20611687 has 2 divisors, whose sum is σ = 20611688. Its totient is φ = 20611686.

The previous prime is 20611681. The next prime is 20611691. The reversal of 20611687 is 78611602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20611687 - 2¹¹ = 20609639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20611681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10305843 + 10305844.

It is an arithmetic number, because the mean of its divisors is an integer number (10305844).

Almost surely, 2^20611687 is an apocalyptic number.

20611687 is a deficient number, since it is larger than the sum of its proper divisors (1).

20611687 is an equidigital number, since it uses as much as digits as its factorization.

20611687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 20611687 is about 4540.0095814877. The cubic root of 20611687 is about 274.1813094834.

The spelling of 20611687 in words is "twenty million, six hundred eleven thousand, six hundred eighty-seven".