869971999 has 4 divisors (see below), whose sum is σ = 936892936. Its totient is φ = 803051064.

The previous prime is 869971979. The next prime is 869972023. The reversal of 869971999 is 999179968.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 869971999 - 2⁷ = 869971871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (869971939) 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, 33460449 + ... + 33460474.

It is an arithmetic number, because the mean of its divisors is an integer number (234223234).

Almost surely, 2^869971999 is an apocalyptic number.

869971999 is a deficient number, since it is larger than the sum of its proper divisors (66920937).

869971999 is a wasteful number, since it uses less digits than its factorization.

869971999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66920936.

The product of its digits is 19840464, while the sum is 67.

The square root of 869971999 is about 29495.2877422818. The cubic root of 869971999 is about 954.6300291088.

The spelling of 869971999 in words is "eight hundred sixty-nine million, nine hundred seventy-one thousand, nine hundred ninety-nine".