20506867 has 8 divisors (see below), whose sum is σ = 20861456. Its totient is φ = 20155392.

The previous prime is 20506861. The next prime is 20506873. The reversal of 20506867 is 76860502.

It is an interprime number because it is at equal distance from previous prime (20506861) and next prime (20506873).

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

It is a 10-Lehmer number, since φ(20506867) divides (20506867-1)¹⁰.

It is a cyclic number.

It is not a de Polignac number, because 20506867 - 2¹⁹ = 19982579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20506861) 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, 15163 + ... + 16459.

It is an arithmetic number, because the mean of its divisors is an integer number (2607682).

Almost surely, 2^20506867 is an apocalyptic number.

20506867 is a deficient number, since it is larger than the sum of its proper divisors (354589).

20506867 is a wasteful number, since it uses less digits than its factorization.

20506867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557.

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 20506867 is about 4528.4508388631. The cubic root of 20506867 is about 273.7157396155.

The spelling of 20506867 in words is "twenty million, five hundred six thousand, eight hundred sixty-seven".