819897639523 has 8 divisors (see below), whose sum is σ = 840015713376. Its totient is φ = 799785307200.

The previous prime is 819897639391. The next prime is 819897639541. The reversal of 819897639523 is 325936798918.

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 819897639523 - 2¹³ = 819897631331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (819897631523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1145568 + ... + 1718173.

It is an arithmetic number, because the mean of its divisors is an integer number (105001964172).

Almost surely, 2^819897639523 is an apocalyptic number.

819897639523 is a deficient number, since it is larger than the sum of its proper divisors (20118073853).

819897639523 is a wasteful number, since it uses less digits than its factorization.

819897639523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2870765.

The product of its digits is 176359680, while the sum is 70.

The spelling of 819897639523 in words is "eight hundred nineteen billion, eight hundred ninety-seven million, six hundred thirty-nine thousand, five hundred twenty-three".