1921913448 has 128 divisors (see below), whose sum is σ = 6104555520. Its totient is φ = 490510080.

The previous prime is 1921913447. The next prime is 1921913453. The reversal of 1921913448 is 8443191291.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (1921913447) 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 31 ways as a sum of consecutive naturals, for example, 53511 + ... + 81897.

It is an arithmetic number, because the mean of its divisors is an integer number (47691840).

Almost surely, 2^1921913448 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 1921913448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3052277760).

1921913448 is an abundant number, since it is smaller than the sum of its proper divisors (4182642072).

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

1921913448 is a wasteful number, since it uses less digits than its factorization.

1921913448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28447 (or 28443 counting only the distinct ones).

The product of its digits is 62208, while the sum is 42.

The square root of 1921913448 is about 43839.6333013861. The cubic root of 1921913448 is about 1243.3057491758.

The spelling of 1921913448 in words is "one billion, nine hundred twenty-one million, nine hundred thirteen thousand, four hundred forty-eight".