20855209397 has 8 divisors (see below), whose sum is σ = 22777819680. Its totient is φ = 18937046160.

The previous prime is 20855209273. The next prime is 20855209399. The reversal of 20855209397 is 79390255802.

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

It is a cyclic number.

It is not a de Polignac number, because 20855209397 - 2¹⁶ = 20855143861 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20855209399) by changing a digit.

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, 1101947 + ... + 1120712.

It is an arithmetic number, because the mean of its divisors is an integer number (2847227460).

Almost surely, 2^20855209397 is an apocalyptic number.

It is an amenable number.

20855209397 is a deficient number, since it is larger than the sum of its proper divisors (1922610283).

20855209397 is a wasteful number, since it uses less digits than its factorization.

20855209397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2223523.

The product of its (nonzero) digits is 1360800, while the sum is 50.

The spelling of 20855209397 in words is "twenty billion, eight hundred fifty-five million, two hundred nine thousand, three hundred ninety-seven".