1661221346 has 16 divisors (see below), whose sum is σ = 2549642400. Its totient is φ = 811513728.

The previous prime is 1661221343. The next prime is 1661221379. The reversal of 1661221346 is 6431221661.

It is not an unprimeable number, because it can be changed into a prime (1661221343) 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, 23951 + ... + 62418.

It is an arithmetic number, because the mean of its divisors is an integer number (159352650).

Almost surely, 2^1661221346 is an apocalyptic number.

1661221346 is a deficient number, since it is larger than the sum of its proper divisors (888421054).

1661221346 is a wasteful number, since it uses less digits than its factorization.

1661221346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86593.

The product of its digits is 10368, while the sum is 32.

The square root of 1661221346 is about 40758.0831983056. The cubic root of 1661221346 is about 1184.3384644002.

The spelling of 1661221346 in words is "one billion, six hundred sixty-one million, two hundred twenty-one thousand, three hundred forty-six".