7921000000 has 147 divisors (see below), whose sum is σ = 19870780807. Its totient is φ = 3132800000.

The previous prime is 7920999913. The next prime is 7921000001. The reversal of 7921000000 is 1297.

The square root of 7921000000 is 89000.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 10 ways, for example, as 4181432896 + 3739567104 = 64664^2 + 61152^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7921000001) 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 20 ways as a sum of consecutive naturals, for example, 88999956 + ... + 89000044.

Almost surely, 2^7921000000 is an apocalyptic number.

7921000000 is the 89000-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7921000000

7921000000 is an abundant number, since it is smaller than the sum of its proper divisors (11949780807).

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

7921000000 is an frugal number, since it uses more digits than its factorization.

7921000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220 (or 96 counting only the distinct ones).

The product of its (nonzero) digits is 126, while the sum is 19.

The cubic root of 7921000000 is about 1993.3948768546.

Adding to 7921000000 its reverse (1297), we get a palindrome (7921001297).

The spelling of 7921000000 in words is "seven billion, nine hundred twenty-one million", and thus it is an aban number.