1921927680 has 120 divisors (see below), whose sum is σ = 6656255892. Its totient is φ = 512507904.

The previous prime is 1921927669. The next prime is 1921927697. The reversal of 1921927680 is 867291291.

1921927680 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 1715947776 + 205979904 = 41424^2 + 14352^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 18669 + ... + 64748.

Almost surely, 2^1921927680 is an apocalyptic number.

1921927680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1921927680 is an abundant number, since it is smaller than the sum of its proper divisors (4734328212).

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

1921927680 is an equidigital number, since it uses as much as digits as its factorization.

1921927680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83446 (or 83427 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 1921927680 is about 43839.7956199616. The cubic root of 1921927680 is about 1243.3088181110.

The spelling of 1921927680 in words is "one billion, nine hundred twenty-one million, nine hundred twenty-seven thousand, six hundred eighty".