15149221 has 4 divisors (see below), whose sum is σ = 15157132. Its totient is φ = 15141312.

The previous prime is 15149209. The next prime is 15149231. The reversal of 15149221 is 12294151.

It is a happy number.

15149221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 9696996 + 5452225 = 3114^2 + 2335^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15149221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15149231) 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, 925 + ... + 5581.

It is an arithmetic number, because the mean of its divisors is an integer number (3789283).

Almost surely, 2^15149221 is an apocalyptic number.

It is an amenable number.

15149221 is a deficient number, since it is larger than the sum of its proper divisors (7911).

15149221 is an equidigital number, since it uses as much as digits as its factorization.

15149221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7910.

The product of its digits is 720, while the sum is 25.

The square root of 15149221 is about 3892.2000205539. The cubic root of 15149221 is about 247.4363118786.

The spelling of 15149221 in words is "fifteen million, one hundred forty-nine thousand, two hundred twenty-one".