221631497 has 8 divisors (see below), whose sum is σ = 224894880. Its totient is φ = 218382400.

The previous prime is 221631463. The next prime is 221631539. The reversal of 221631497 is 794136122.

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 221631497 - 2¹⁴ = 221615113 is a prime.

It is a super-2 number, since 2×221631497² = 98241040924922018, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221631407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29954 + ... + 36612.

It is an arithmetic number, because the mean of its divisors is an integer number (28111860).

Almost surely, 2^221631497 is an apocalyptic number.

It is an amenable number.

221631497 is a deficient number, since it is larger than the sum of its proper divisors (3263383).

221631497 is an equidigital number, since it uses as much as digits as its factorization.

221631497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7143.

The product of its digits is 18144, while the sum is 35.

The square root of 221631497 is about 14887.2931387811. The cubic root of 221631497 is about 605.1696785191.

The spelling of 221631497 in words is "two hundred twenty-one million, six hundred thirty-one thousand, four hundred ninety-seven".