7121571840 has 468 divisors, whose sum is σ = 26116872444. Its totient is φ = 1863254016.

The previous prime is 7121571827. The next prime is 7121571851. The reversal of 7121571840 is 481751217.

7121571840 is a `hidden beast` number, since 7 + 1 + 2 + 1 + 571 + 84 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3869835264 + 3251736576 = 62208^2 + 57024^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 7121571795 and 7121571804.

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 35 ways as a sum of consecutive naturals, for example, 134369254 + ... + 134369306.

It is an arithmetic number, because the mean of its divisors is an integer number (55805283).

Almost surely, 2^7121571840 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 7121571840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13058436222).

7121571840 is an abundant number, since it is smaller than the sum of its proper divisors (18995300604).

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

7121571840 is an frugal number, since it uses more digits than its factorization.

7121571840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 36.

The square root of 7121571840 is about 84389.4059701809. The cubic root of 7121571840 is about 1923.9419014474.

The spelling of 7121571840 in words is "seven billion, one hundred twenty-one million, five hundred seventy-one thousand, eight hundred forty".