221961331 has 8 divisors (see below), whose sum is σ = 235216800. Its totient is φ = 209079360.

The previous prime is 221961319. The next prime is 221961353. The reversal of 221961331 is 133169122.

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 221961331 - 2¹⁹ = 221437043 is a prime.

It is a super-2 number, since 2×221961331² = 98533664918583122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221961331.

It is not an unprimeable number, because it can be changed into a prime (221961301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 92151 + ... + 94528.

It is an arithmetic number, because the mean of its divisors is an integer number (29402100).

Almost surely, 2^221961331 is an apocalyptic number.

221961331 is a deficient number, since it is larger than the sum of its proper divisors (13255469).

221961331 is a wasteful number, since it uses less digits than its factorization.

221961331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186749.

The product of its digits is 1944, while the sum is 28.

The square root of 221961331 is about 14898.3667225639. The cubic root of 221961331 is about 605.4697360500.

The spelling of 221961331 in words is "two hundred twenty-one million, nine hundred sixty-one thousand, three hundred thirty-one".