19248457721 has 8 divisors (see below), whose sum is σ = 19871414784. Its totient is φ = 18625628160.

The previous prime is 19248457703. The next prime is 19248457733. The reversal of 19248457721 is 12775484291.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19248457721 - 2²² = 19244263417 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19248457721.

It is not an unprimeable number, because it can be changed into a prime (19248457021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 346361 + ... + 398073.

It is an arithmetic number, because the mean of its divisors is an integer number (2483926848).

Almost surely, 2^19248457721 is an apocalyptic number.

It is an amenable number.

19248457721 is a deficient number, since it is larger than the sum of its proper divisors (622957063).

19248457721 is a wasteful number, since it uses less digits than its factorization.

19248457721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63751.

The product of its digits is 1128960, while the sum is 50.

The spelling of 19248457721 in words is "nineteen billion, two hundred forty-eight million, four hundred fifty-seven thousand, seven hundred twenty-one".