8397817855321 has 4 divisors (see below), whose sum is σ = 8448104189952. Its totient is φ = 8347531520692.

The previous prime is 8397817855211. The next prime is 8397817855331. The reversal of 8397817855321 is 1235587187938.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 8397817855321 - 2¹³ = 8397817847129 is a prime.

It is a super-2 number, since 2×8397817855321² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8397817855331) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25143167065 + ... + 25143167398.

It is an arithmetic number, because the mean of its divisors is an integer number (2112026047488).

Almost surely, 2^{8397817855321} is an apocalyptic number.

It is an amenable number.

8397817855321 is a deficient number, since it is larger than the sum of its proper divisors (50286334631).

8397817855321 is a wasteful number, since it uses less digits than its factorization.

8397817855321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50286334630.

The product of its digits is 101606400, while the sum is 67.

The spelling of 8397817855321 in words is "eight trillion, three hundred ninety-seven billion, eight hundred seventeen million, eight hundred fifty-five thousand, three hundred twenty-one".