20655845670 has 64 divisors (see below), whose sum is σ = 50313369600. Its totient is φ = 5426258688.

The previous prime is 20655845669. The next prime is 20655845701. The reversal of 20655845670 is 7654855602.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1981131 + ... + 1991529.

It is an arithmetic number, because the mean of its divisors is an integer number (786146400).

Almost surely, 2^20655845670 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20655845670, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25156684800).

20655845670 is an abundant number, since it is smaller than the sum of its proper divisors (29657523930).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20655845670 is a wasteful number, since it uses less digits than its factorization.

20655845670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11389.

The product of its (nonzero) digits is 2016000, while the sum is 48.

The spelling of 20655845670 in words is "twenty billion, six hundred fifty-five million, eight hundred forty-five thousand, six hundred seventy".