1916408720 has 20 divisors (see below), whose sum is σ = 4455650460. Its totient is φ = 766563456.

The previous prime is 1916408717. The next prime is 1916408729. The reversal of 1916408720 is 278046191.

It can be written as a sum of positive squares in 2 ways, for example, as 1225560064 + 690848656 = 35008^2 + 26284^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (1916408729) 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 3 ways as a sum of consecutive naturals, for example, 11977475 + ... + 11977634.

It is an arithmetic number, because the mean of its divisors is an integer number (222782523).

Almost surely, 2^1916408720 is an apocalyptic number.

1916408720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1916408720 is an abundant number, since it is smaller than the sum of its proper divisors (2539241740).

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

1916408720 is a wasteful number, since it uses less digits than its factorization.

1916408720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23955122 (or 23955116 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 38.

The square root of 1916408720 is about 43776.8057308890. The cubic root of 1916408720 is about 1242.1175921983.

The spelling of 1916408720 in words is "one billion, nine hundred sixteen million, four hundred eight thousand, seven hundred twenty".