1661056012 has 48 divisors (see below), whose sum is σ = 3741050880. Its totient is φ = 626284800.

The previous prime is 1661055989. The next prime is 1661056051. The reversal of 1661056012 is 2106501661.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77437 + ... + 96532.

It is an arithmetic number, because the mean of its divisors is an integer number (77938560).

Almost surely, 2^1661056012 is an apocalyptic number.

It is an amenable number.

1661056012 is an abundant number, since it is smaller than the sum of its proper divisors (2079994868).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661056012 is a wasteful number, since it uses less digits than its factorization.

1661056012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174022 (or 174020 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 1661056012 is about 40756.0549121232. The cubic root of 1661056012 is about 1184.2991724434.

Adding to 1661056012 its reverse (2106501661), we get a palindrome (3767557673).

The spelling of 1661056012 in words is "one billion, six hundred sixty-one million, fifty-six thousand, twelve".