221136491 has 8 divisors (see below), whose sum is σ = 224557440. Its totient is φ = 217726272.

The previous prime is 221136479. The next prime is 221136523. The reversal of 221136491 is 194631122.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221136491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221136451) 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, 45350 + ... + 49988.

It is an arithmetic number, because the mean of its divisors is an integer number (28069680).

Almost surely, 2^221136491 is an apocalyptic number.

221136491 is a deficient number, since it is larger than the sum of its proper divisors (3420949).

221136491 is an equidigital number, since it uses as much as digits as its factorization.

221136491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5365.

The product of its digits is 2592, while the sum is 29.

The square root of 221136491 is about 14870.6587278439. The cubic root of 221136491 is about 604.7188010883.

The spelling of 221136491 in words is "two hundred twenty-one million, one hundred thirty-six thousand, four hundred ninety-one".