820128867 has 8 divisors (see below), whose sum is σ = 1100747520. Its totient is φ = 543131400.

The previous prime is 820128857. The next prime is 820128877. The reversal of 820128867 is 768821028.

It is an interprime number because it is at equal distance from previous prime (820128857) and next prime (820128877).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 820128867 - 2¹⁰ = 820127843 is a prime.

It is a super-2 number, since 2×820128867² = 1345222716973407378, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (820128847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 904767 + ... + 905672.

It is an arithmetic number, because the mean of its divisors is an integer number (137593440).

Almost surely, 2^820128867 is an apocalyptic number.

820128867 is a deficient number, since it is larger than the sum of its proper divisors (280618653).

820128867 is a wasteful number, since it uses less digits than its factorization.

820128867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1810593.

The product of its (nonzero) digits is 86016, while the sum is 42.

The square root of 820128867 is about 28637.8921535786. The cubic root of 820128867 is about 936.0391915524.

The spelling of 820128867 in words is "eight hundred twenty million, one hundred twenty-eight thousand, eight hundred sixty-seven".