19740241921 has 4 divisors (see below), whose sum is σ = 19747857412. Its totient is φ = 19732626432.

The previous prime is 19740241879. The next prime is 19740241973. The reversal of 19740241921 is 12914204791.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15200177521 + 4540064400 = 123289^2 + 67380^2 .

It is a cyclic number.

It is not a de Polignac number, because 19740241921 - 2⁷ = 19740241793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19740241621) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 3803856 + ... + 3809041.

It is an arithmetic number, because the mean of its divisors is an integer number (4936964353).

Almost surely, 2^19740241921 is an apocalyptic number.

It is an amenable number.

19740241921 is a deficient number, since it is larger than the sum of its proper divisors (7615491).

19740241921 is an equidigital number, since it uses as much as digits as its factorization.

19740241921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7615490.

The product of its (nonzero) digits is 36288, while the sum is 40.

The spelling of 19740241921 in words is "nineteen billion, seven hundred forty million, two hundred forty-one thousand, nine hundred twenty-one".