15221091 has 8 divisors (see below), whose sum is σ = 20726784. Its totient is φ = 9931400.

The previous prime is 15221083. The next prime is 15221099. The reversal of 15221091 is 19012251.

It is an interprime number because it is at equal distance from previous prime (15221083) and next prime (15221099).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 15221091 - 2³ = 15221083 is a prime.

It is a super-2 number, since 2×15221091² = 463363222460562, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (15221099) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53835 + ... + 54116.

It is an arithmetic number, because the mean of its divisors is an integer number (2590848).

Almost surely, 2^15221091 is an apocalyptic number.

15221091 is a deficient number, since it is larger than the sum of its proper divisors (5505693).

15221091 is a wasteful number, since it uses less digits than its factorization.

15221091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108001.

The product of its (nonzero) digits is 180, while the sum is 21.

The square root of 15221091 is about 3901.4216639579. The cubic root of 15221091 is about 247.8269854224.

The spelling of 15221091 in words is "fifteen million, two hundred twenty-one thousand, ninety-one".