15221355 has 16 divisors (see below), whose sum is σ = 24921600. Its totient is φ = 7928928.

The previous prime is 15221347. The next prime is 15221357. The reversal of 15221355 is 55312251.

It is a happy number.

It is not a de Polignac number, because 15221355 - 2³ = 15221347 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15221357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11155 + ... + 12444.

It is an arithmetic number, because the mean of its divisors is an integer number (1557600).

Almost surely, 2^15221355 is an apocalyptic number.

15221355 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

15221355 is a deficient number, since it is larger than the sum of its proper divisors (9700245).

15221355 is a wasteful number, since it uses less digits than its factorization.

15221355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23650.

The product of its digits is 1500, while the sum is 24.

The square root of 15221355 is about 3901.4554976316. The cubic root of 15221355 is about 247.8284182138.

It can be divided in two parts, 15221 and 355, that added together give a triangular number (15576 = T₁₇₆).

The spelling of 15221355 in words is "fifteen million, two hundred twenty-one thousand, three hundred fifty-five".