1661783216 has 10 divisors (see below), whose sum is σ = 3219705012. Its totient is φ = 830891600.

The previous prime is 1661783213. The next prime is 1661783231. The reversal of 1661783216 is 6123871661.

It is not an unprimeable number, because it can be changed into a prime (1661783213) 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 as a sum of consecutive naturals, namely, 51930710 + ... + 51930741.

Almost surely, 2^1661783216 is an apocalyptic number.

1661783216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1661783216 is a deficient number, since it is larger than the sum of its proper divisors (1557921796).

1661783216 is a wasteful number, since it uses less digits than its factorization.

1661783216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103861459 (or 103861453 counting only the distinct ones).

The product of its digits is 72576, while the sum is 41.

The square root of 1661783216 is about 40764.9753587562. The cubic root of 1661783216 is about 1184.4719744519.

The spelling of 1661783216 in words is "one billion, six hundred sixty-one million, seven hundred eighty-three thousand, two hundred sixteen".