15243454421 has 4 divisors (see below), whose sum is σ = 16416027852. Its totient is φ = 14070880992.

The previous prime is 15243454403. The next prime is 15243454427. The reversal of 15243454421 is 12445434251.

It is a happy number.

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 1551178225 + 13692276196 = 39385^2 + 117014^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15243454421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15243454427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 586286696 + ... + 586286721.

It is an arithmetic number, because the mean of its divisors is an integer number (4104006963).

Almost surely, 2^15243454421 is an apocalyptic number.

It is an amenable number.

15243454421 is a deficient number, since it is larger than the sum of its proper divisors (1172573431).

15243454421 is a wasteful number, since it uses less digits than its factorization.

15243454421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1172573430.

The product of its digits is 76800, while the sum is 35.

Adding to 15243454421 its reverse (12445434251), we get a palindrome (27688888672).

The spelling of 15243454421 in words is "fifteen billion, two hundred forty-three million, four hundred fifty-four thousand, four hundred twenty-one".