7121856 has 84 divisors (see below), whose sum is σ = 21948648. Its totient is φ = 2032128.

The previous prime is 7121839. The next prime is 7121867. The reversal of 7121856 is 6581217.

It is a tau number, because it is divible by the number of its divisors (84).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9030 + ... + 9786.

Almost surely, 2^7121856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7121856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10974324).

7121856 is an abundant number, since it is smaller than the sum of its proper divisors (14826792).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7121856 is a wasteful number, since it uses less digits than its factorization.

7121856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 786 (or 769 counting only the distinct ones).

The product of its digits is 3360, while the sum is 30.

The square root of 7121856 is about 2668.6805728674. The cubic root of 7121856 is about 192.3967490370.

The spelling of 7121856 in words is "seven million, one hundred twenty-one thousand, eight hundred fifty-six".