869805891 has 16 divisors (see below), whose sum is σ = 1294237600. Its totient is φ = 577334304.

The previous prime is 869805847. The next prime is 869805899. The reversal of 869805891 is 198508968.

It is not a de Polignac number, because 869805891 - 2¹⁰ = 869804867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (869805899) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64156 + ... + 76521.

It is an arithmetic number, because the mean of its divisors is an integer number (80889850).

Almost surely, 2^869805891 is an apocalyptic number.

869805891 is a deficient number, since it is larger than the sum of its proper divisors (424431709).

869805891 is a wasteful number, since it uses less digits than its factorization.

869805891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140915 (or 140909 counting only the distinct ones).

The product of its (nonzero) digits is 1244160, while the sum is 54.

The square root of 869805891 is about 29492.4717682327. The cubic root of 869805891 is about 954.5692678512.

The spelling of 869805891 in words is "eight hundred sixty-nine million, eight hundred five thousand, eight hundred ninety-one".