20617655 has 4 divisors (see below), whose sum is σ = 24741192. Its totient is φ = 16494120.

The previous prime is 20617643. The next prime is 20617669. The reversal of 20617655 is 55671602.

It is a happy number.

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

It is not a de Polignac number, because 20617655 - 2¹⁴ = 20601271 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2061761 + ... + 2061770.

It is an arithmetic number, because the mean of its divisors is an integer number (6185298).

Almost surely, 2^20617655 is an apocalyptic number.

20617655 is a deficient number, since it is larger than the sum of its proper divisors (4123537).

20617655 is an equidigital number, since it uses as much as digits as its factorization.

20617655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4123536.

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 20617655 is about 4540.6668012529. Note that the first 3 decimals coincide. The cubic root of 20617655 is about 274.2077694905.

The spelling of 20617655 in words is "twenty million, six hundred seventeen thousand, six hundred fifty-five".