1921040004 has 48 divisors (see below), whose sum is σ = 4842774272. Its totient is φ = 589185792.

The previous prime is 1921040003. The next prime is 1921040027. The reversal of 1921040004 is 4000401291.

It is not an unprimeable number, because it can be changed into a prime (1921040003) 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 15 ways as a sum of consecutive naturals, for example, 29157 + ... + 68499.

Almost surely, 2^1921040004 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 1921040004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2421387136).

1921040004 is an abundant number, since it is smaller than the sum of its proper divisors (2921734268).

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

1921040004 is a wasteful number, since it uses less digits than its factorization.

1921040004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39676 (or 39674 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 1921040004 is about 43829.6703615256. The cubic root of 1921040004 is about 1243.1173739744.

Adding to 1921040004 its reverse (4000401291), we get a palindrome (5921441295).

The spelling of 1921040004 in words is "one billion, nine hundred twenty-one million, forty thousand, four".