20881920346506 has 16 divisors (see below), whose sum is σ = 46404267436800. Its totient is φ = 6960640115484.

The previous prime is 20881920346489. The next prime is 20881920346517. The reversal of 20881920346506 is 60564302918802.

20881920346506 is a `hidden beast` number, since 2 + 0 + 8 + 8 + 1 + 92 + 0 + 3 + 46 + 506 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54), and also a Moran number because the ratio is a prime number: 386702228639 = 20881920346506 / (2 + 0 + 8 + 8 + 1 + 9 + 2 + 0 + 3 + 4 + 6 + 5 + 0 + 6).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 193351114266 + ... + 193351114373.

It is an arithmetic number, because the mean of its divisors is an integer number (2900266714800).

Almost surely, 2^{20881920346506} is an apocalyptic number.

20881920346506 is an abundant number, since it is smaller than the sum of its proper divisors (25522347090294).

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

20881920346506 is a wasteful number, since it uses less digits than its factorization.

20881920346506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386702228650 (or 386702228644 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 20881920346506 in words is "twenty trillion, eight hundred eighty-one billion, nine hundred twenty million, three hundred forty-six thousand, five hundred six".