221854971 has 16 divisors (see below), whose sum is σ = 319964960. Its totient is φ = 135924480.

The previous prime is 221854967. The next prime is 221855021. The reversal of 221854971 is 179458122.

It is not a de Polignac number, because 221854971 - 2² = 221854967 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221854961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3490 + ... + 21351.

It is an arithmetic number, because the mean of its divisors is an integer number (19997810).

Almost surely, 2^221854971 is an apocalyptic number.

221854971 is a deficient number, since it is larger than the sum of its proper divisors (98109989).

221854971 is a wasteful number, since it uses less digits than its factorization.

221854971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25086.

The product of its digits is 40320, while the sum is 39.

The square root of 221854971 is about 14894.7967760557. The cubic root of 221854971 is about 605.3730104181.

The spelling of 221854971 in words is "two hundred twenty-one million, eight hundred fifty-four thousand, nine hundred seventy-one".