15464221 has 4 divisors (see below), whose sum is σ = 15997500. Its totient is φ = 14930944.

The previous prime is 15464213. The next prime is 15464227. The reversal of 15464221 is 12246451.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12246451 = 7 ⋅1749493.

It can be written as a sum of positive squares in 2 ways, for example, as 7562500 + 7901721 = 2750^2 + 2811^2 .

It is a cyclic number.

It is not a de Polignac number, because 15464221 - 2³ = 15464213 is a prime.

It is a super-2 number, since 2×15464221² = 478284262273682, which 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 (15464227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 266596 + ... + 266653.

It is an arithmetic number, because the mean of its divisors is an integer number (3999375).

Almost surely, 2^15464221 is an apocalyptic number.

It is an amenable number.

15464221 is a deficient number, since it is larger than the sum of its proper divisors (533279).

15464221 is an equidigital number, since it uses as much as digits as its factorization.

15464221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533278.

The product of its digits is 1920, while the sum is 25.

The square root of 15464221 is about 3932.4573742127. The cubic root of 15464221 is about 249.1395539278.

The spelling of 15464221 in words is "fifteen million, four hundred sixty-four thousand, two hundred twenty-one".