15523452421 has 8 divisors (see below), whose sum is σ = 15587645184. Its totient is φ = 15459390960.

The previous prime is 15523452397. The next prime is 15523452457. The reversal of 15523452421 is 12425432551.

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 15523452421 - 2¹³ = 15523444229 is a prime.

It is a super-2 number, since 2×15523452421² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15526452421) 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, 207736 + ... + 272398.

It is an arithmetic number, because the mean of its divisors is an integer number (1948455648).

Almost surely, 2^15523452421 is an apocalyptic number.

It is an amenable number.

15523452421 is a deficient number, since it is larger than the sum of its proper divisors (64192763).

15523452421 is an equidigital number, since it uses as much as digits as its factorization.

15523452421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65651.

The product of its digits is 48000, while the sum is 34.

Adding to 15523452421 its reverse (12425432551), we get a palindrome (27948884972).

The spelling of 15523452421 in words is "fifteen billion, five hundred twenty-three million, four hundred fifty-two thousand, four hundred twenty-one".