15221413 has 4 divisors (see below), whose sum is σ = 16022560. Its totient is φ = 14420268.

The previous prime is 15221411. The next prime is 15221417. The reversal of 15221413 is 31412251.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 31412251 = 13 ⋅2416327.

It is a cyclic number.

It is not a de Polignac number, because 15221413 - 2¹ = 15221411 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 801127 = 15221413 / (1 + 5 + 2 + 2 + 1 + 4 + 1 + 3).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15221411) 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, 400545 + ... + 400582.

It is an arithmetic number, because the mean of its divisors is an integer number (4005640).

Almost surely, 2^15221413 is an apocalyptic number.

It is an amenable number.

15221413 is a deficient number, since it is larger than the sum of its proper divisors (801147).

15221413 is an equidigital number, since it uses as much as digits as its factorization.

15221413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 801146.

The product of its digits is 240, while the sum is 19.

The square root of 15221413 is about 3901.4629307479. The cubic root of 15221413 is about 247.8287329915.

Adding to 15221413 its reverse (31412251), we get a palindrome (46633664).

The spelling of 15221413 in words is "fifteen million, two hundred twenty-one thousand, four hundred thirteen".