20686671 has 40 divisors (see below), whose sum is σ = 33297264. Its totient is φ = 12752640.

The previous prime is 20686661. The next prime is 20686681. The reversal of 20686671 is 17668602.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20686661) and next prime (20686681).

It is not a de Polignac number, because 20686671 - 2⁶ = 20686607 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20686621) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 114201 + ... + 114381.

Almost surely, 2^20686671 is an apocalyptic number.

20686671 is a deficient number, since it is larger than the sum of its proper divisors (12610593).

20686671 is a wasteful number, since it uses less digits than its factorization.

20686671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293 (or 284 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 20686671 is about 4548.2602168302. The cubic root of 20686671 is about 274.5133918039.

The spelling of 20686671 in words is "twenty million, six hundred eighty-six thousand, six hundred seventy-one".