20671587 has 12 divisors (see below), whose sum is σ = 30494880. Its totient is φ = 13487568.

The previous prime is 20671543. The next prime is 20671603. The reversal of 20671587 is 78517602.

20671587 is a `hidden beast` number, since 2 + 0 + 6 + 71 + 587 = 666.

It is not a de Polignac number, because 20671587 - 2⁸ = 20671331 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20671517) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24012 + ... + 24857.

It is an arithmetic number, because the mean of its divisors is an integer number (2541240).

Almost surely, 2^20671587 is an apocalyptic number.

20671587 is a deficient number, since it is larger than the sum of its proper divisors (9823293).

20671587 is a wasteful number, since it uses less digits than its factorization.

20671587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48922 (or 48919 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

The square root of 20671587 is about 4546.6016979718. The cubic root of 20671587 is about 274.4466537121.

The spelling of 20671587 in words is "twenty million, six hundred seventy-one thousand, five hundred eighty-seven".