855642839489 has 4 divisors (see below), whose sum is σ = 883244221440. Its totient is φ = 828041457540.

The previous prime is 855642839479. The next prime is 855642839539. The reversal of 855642839489 is 984938246558.

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 a de Polignac number, because none of the positive numbers 2^k-855642839489 is a prime.

It is a super-2 number, since 2×855642839489² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (855642839419) 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, 13800690929 + ... + 13800690990.

It is an arithmetic number, because the mean of its divisors is an integer number (220811055360).

Almost surely, 2^855642839489 is an apocalyptic number.

It is an amenable number.

855642839489 is a deficient number, since it is larger than the sum of its proper divisors (27601381951).

855642839489 is a wasteful number, since it uses less digits than its factorization.

855642839489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27601381950.

The product of its digits is 597196800, while the sum is 71.

The spelling of 855642839489 in words is "eight hundred fifty-five billion, six hundred forty-two million, eight hundred thirty-nine thousand, four hundred eighty-nine".