285779489921 has 4 divisors (see below), whose sum is σ = 285892404144. Its totient is φ = 285666575700.

The previous prime is 285779489903. The next prime is 285779489923. The reversal of 285779489921 is 129984977582.

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, and also an emirpimes, since its reverse is a distinct semiprime: 129984977582 = 2 ⋅64992488791.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-285779489921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (285779489923) 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, 56453315 + ... + 56458376.

It is an arithmetic number, because the mean of its divisors is an integer number (71473101036).

Almost surely, 2^285779489921 is an apocalyptic number.

It is an amenable number.

285779489921 is a deficient number, since it is larger than the sum of its proper divisors (112914223).

285779489921 is a wasteful number, since it uses less digits than its factorization.

285779489921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112914222.

The product of its digits is 182891520, while the sum is 71.

The spelling of 285779489921 in words is "two hundred eighty-five billion, seven hundred seventy-nine million, four hundred eighty-nine thousand, nine hundred twenty-one".