1066616221 has 4 divisors (see below), whose sum is σ = 1163581344. Its totient is φ = 969651100.

The previous prime is 1066616203. The next prime is 1066616249. The reversal of 1066616221 is 1226166601.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1066616221 - 2⁷ = 1066616093 is a prime.

It is a super-2 number, since 2×1066616221² = 2275340325800641682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1066616021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48482545 + ... + 48482566.

It is an arithmetic number, because the mean of its divisors is an integer number (290895336).

Almost surely, 2^1066616221 is an apocalyptic number.

1066616221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1066616221 is a deficient number, since it is larger than the sum of its proper divisors (96965123).

1066616221 is an equidigital number, since it uses as much as digits as its factorization.

1066616221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96965122.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 1066616221 is about 32659.0909395837. The cubic root of 1066616221 is about 1021.7298025249.

The spelling of 1066616221 in words is "one billion, sixty-six million, six hundred sixteen thousand, two hundred twenty-one".