84559405681 has 3 divisors (see below), whose sum is σ = 84559696473. Its totient is φ = 84559114890.

The previous prime is 84559405661. The next prime is 84559405687. The reversal of 84559405681 is 18650495548.

The square root of 84559405681 is 290791.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 84559405681 - 2²⁷ = 84425187953 is a prime.

It is a super-2 number, since 2×84559405681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84559405687) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 145396 + ... + 436186.

It is an arithmetic number, because the mean of its divisors is an integer number (28186565491).

Almost surely, 2^84559405681 is an apocalyptic number.

84559405681 is the 290791-st square number.

84559405681 is the 145396-th centered octagonal number.

It is an amenable number.

84559405681 is a deficient number, since it is larger than the sum of its proper divisors (290792).

84559405681 is an frugal number, since it uses more digits than its factorization.

84559405681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 581582 (or 290791 counting only the distinct ones).

The product of its (nonzero) digits is 6912000, while the sum is 55.

The spelling of 84559405681 in words is "eighty-four billion, five hundred fifty-nine million, four hundred five thousand, six hundred eighty-one".