1866071221 has 8 divisors (see below), whose sum is σ = 2178028800. Its totient is φ = 1565457648.

The previous prime is 1866071197. The next prime is 1866071227. The reversal of 1866071221 is 1221706681.

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 1866071221 - 2¹⁷ = 1865940149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1866071227) 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, 2835646 + ... + 2836303.

It is an arithmetic number, because the mean of its divisors is an integer number (272253600).

Almost surely, 2^1866071221 is an apocalyptic number.

It is an amenable number.

1866071221 is a deficient number, since it is larger than the sum of its proper divisors (311957579).

1866071221 is an equidigital number, since it uses as much as digits as its factorization.

1866071221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5672003.

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 1866071221 is about 43198.0464951831. The cubic root of 1866071221 is about 1231.1455652581.

The spelling of 1866071221 in words is "one billion, eight hundred sixty-six million, seventy-one thousand, two hundred twenty-one".