20617667 has 4 divisors (see below), whose sum is σ = 23563056. Its totient is φ = 17672280.

The previous prime is 20617643. The next prime is 20617669. The reversal of 20617667 is 76671602.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20617667 - 2⁸ = 20617411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20617669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1472684 + ... + 1472697.

It is an arithmetic number, because the mean of its divisors is an integer number (5890764).

Almost surely, 2^20617667 is an apocalyptic number.

20617667 is a deficient number, since it is larger than the sum of its proper divisors (2945389).

20617667 is an equidigital number, since it uses as much as digits as its factorization.

20617667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2945388.

The product of its (nonzero) digits is 21168, while the sum is 35.

The square root of 20617667 is about 4540.6681226445. The cubic root of 20617667 is about 274.2078226891.

The spelling of 20617667 in words is "twenty million, six hundred seventeen thousand, six hundred sixty-seven".