661222005 has 32 divisors (see below), whose sum is σ = 1104417408. Its totient is φ = 337478400.

The previous prime is 661221989. The next prime is 661222039. The reversal of 661222005 is 500222166.

It is not a de Polignac number, because 661222005 - 2⁴ = 661221989 is a prime.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 24090 + ... + 43620.

It is an arithmetic number, because the mean of its divisors is an integer number (34513044).

Almost surely, 2^661222005 is an apocalyptic number.

It is an amenable number.

661222005 is a deficient number, since it is larger than the sum of its proper divisors (443195403).

661222005 is a wasteful number, since it uses less digits than its factorization.

661222005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19637.

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 661222005 is about 25714.2373987641. The cubic root of 661222005 is about 871.1957859869.

The spelling of 661222005 in words is "six hundred sixty-one million, two hundred twenty-two thousand, five".