15232421 has 2 divisors, whose sum is σ = 15232422. Its totient is φ = 15232420.

The previous prime is 15232397. The next prime is 15232429. The reversal of 15232421 is 12423251.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10562500 + 4669921 = 3250^2 + 2161^2 .

It is an emirp because it is prime and its reverse (12423251) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15232421 - 2¹⁰ = 15231397 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 15232393 and 15232402.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15232429) 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 as a sum of consecutive naturals, namely, 7616210 + 7616211.

It is an arithmetic number, because the mean of its divisors is an integer number (7616211).

Almost surely, 2^15232421 is an apocalyptic number.

It is an amenable number.

15232421 is a deficient number, since it is larger than the sum of its proper divisors (1).

15232421 is an equidigital number, since it uses as much as digits as its factorization.

15232421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 480, while the sum is 20.

The square root of 15232421 is about 3902.8734286420. The cubic root of 15232421 is about 247.8884611589. Note that the first 3 decimals are identical.

Adding to 15232421 its reverse (12423251), we get a palindrome (27655672).

The spelling of 15232421 in words is "fifteen million, two hundred thirty-two thousand, four hundred twenty-one".