20005646555 has 8 divisors (see below), whose sum is σ = 24132466944. Its totient is φ = 15920723200.

The previous prime is 20005646543. The next prime is 20005646579. The reversal of 20005646555 is 55564650002.

It is a happy number.

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

It is not a de Polignac number, because 20005646555 - 2¹⁰ = 20005645531 is a prime.

It is a super-3 number, since 3×20005646555³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10473206 + ... + 10475115.

It is an arithmetic number, because the mean of its divisors is an integer number (3016558368).

Almost surely, 2^20005646555 is an apocalyptic number.

20005646555 is a deficient number, since it is larger than the sum of its proper divisors (4126820389).

20005646555 is a wasteful number, since it uses less digits than its factorization.

20005646555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20948517.

The product of its (nonzero) digits is 180000, while the sum is 38.

The spelling of 20005646555 in words is "twenty billion, five million, six hundred forty-six thousand, five hundred fifty-five".