221978953 has 8 divisors (see below), whose sum is σ = 253812608. Its totient is φ = 190175904.

The previous prime is 221978929. The next prime is 221978959. The reversal of 221978953 is 359879122.

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 221978953 - 2⁵ = 221978921 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221978959) 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, 10900 + ... + 23722.

It is an arithmetic number, because the mean of its divisors is an integer number (31726576).

Almost surely, 2^221978953 is an apocalyptic number.

It is an amenable number.

221978953 is a deficient number, since it is larger than the sum of its proper divisors (31833655).

221978953 is a wasteful number, since it uses less digits than its factorization.

221978953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15303.

The product of its digits is 272160, while the sum is 46.

The square root of 221978953 is about 14898.9581179356. The cubic root of 221978953 is about 605.4857588189.

The spelling of 221978953 in words is "two hundred twenty-one million, nine hundred seventy-eight thousand, nine hundred fifty-three".