9920871 has 12 divisors (see below), whose sum is σ = 14824680. Its totient is φ = 6385680.

The previous prime is 9920863. The next prime is 9920873. The reversal of 9920871 is 1780299.

It is a happy number.

It is not a de Polignac number, because 9920871 - 2³ = 9920863 is a prime.

It is an Ulam number.

9920871 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9920873) 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 11 ways as a sum of consecutive naturals, for example, 18745 + ... + 19266.

It is an arithmetic number, because the mean of its divisors is an integer number (1235390).

Almost surely, 2^9920871 is an apocalyptic number.

9920871 is a deficient number, since it is larger than the sum of its proper divisors (4903809).

9920871 is a wasteful number, since it uses less digits than its factorization.

9920871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38046 (or 38043 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 9920871 is about 3149.7414179580. The cubic root of 9920871 is about 214.8737026400.

The spelling of 9920871 in words is "nine million, nine hundred twenty thousand, eight hundred seventy-one".