20920706406 has 44 divisors (see below), whose sum is σ = 47071589412. Its totient is φ = 6973568802.

The previous prime is 20920706369. The next prime is 20920706437. The reversal of 20920706406 is 60460702902.

It is a happy number.

20920706406 is a `hidden beast` number, since 2 + 0 + 9 + 2 + 0 + 7 + 0 + 640 + 6 = 666.

It is a nialpdrome in base 3 and base 9.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 21 ways as a sum of consecutive naturals, for example, 6973568801 + 6973568802 + 6973568803.

Almost surely, 2^20920706406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20920706406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23535794706).

20920706406 is an abundant number, since it is smaller than the sum of its proper divisors (26150883006).

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

20920706406 is an frugal number, since it uses more digits than its factorization.

20920706406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65 (or 5 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The spelling of 20920706406 in words is "twenty billion, nine hundred twenty million, seven hundred six thousand, four hundred six".