21655106673 has 16 divisors (see below), whose sum is σ = 28973671872. Its totient is φ = 14386680000.

The previous prime is 21655106663. The next prime is 21655106687. The reversal of 21655106673 is 37660155612.

It is not a de Polignac number, because 21655106673 - 2¹⁶ = 21655041137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21655106663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3433623 + ... + 3439923.

It is an arithmetic number, because the mean of its divisors is an integer number (1810854492).

Almost surely, 2^21655106673 is an apocalyptic number.

It is an amenable number.

21655106673 is a deficient number, since it is larger than the sum of its proper divisors (7318565199).

21655106673 is a wasteful number, since it uses less digits than its factorization.

21655106673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10096.

The product of its (nonzero) digits is 226800, while the sum is 42.

The spelling of 21655106673 in words is "twenty-one billion, six hundred fifty-five million, one hundred six thousand, six hundred seventy-three".