20670871 has 8 divisors (see below), whose sum is σ = 22357440. Its totient is φ = 18998112.

The previous prime is 20670863. The next prime is 20670877. The reversal of 20670871 is 17807602.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20670871 - 2³ = 20670863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20670877) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 220 + ... + 6433.

It is an arithmetic number, because the mean of its divisors is an integer number (2794680).

Almost surely, 2^20670871 is an apocalyptic number.

20670871 is a deficient number, since it is larger than the sum of its proper divisors (1686569).

20670871 is a wasteful number, since it uses less digits than its factorization.

20670871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6905.

The product of its (nonzero) digits is 4704, while the sum is 31.

The square root of 20670871 is about 4546.5229571619. The cubic root of 20670871 is about 274.4434850137.

The spelling of 20670871 in words is "twenty million, six hundred seventy thousand, eight hundred seventy-one".