1665656156412 has 72 divisors (see below), whose sum is σ = 4467892805376. Its totient is φ = 542306641968.

The previous prime is 1665656156399. The next prime is 1665656156473. The reversal of 1665656156412 is 2146516565661.

1665656156412 is a `hidden beast` number, since 1 + 6 + 6 + 5 + 6 + 5 + 61 + 564 + 12 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19884228 + ... + 19967819.

Almost surely, 2^{1665656156412} is an apocalyptic number.

1665656156412 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1665656156412 is an abundant number, since it is smaller than the sum of its proper divisors (2802236648964).

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

1665656156412 is a wasteful number, since it uses less digits than its factorization.

1665656156412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39852109 (or 39852095 counting only the distinct ones).

The product of its digits is 7776000, while the sum is 54.

The spelling of 1665656156412 in words is "one trillion, six hundred sixty-five billion, six hundred fifty-six million, one hundred fifty-six thousand, four hundred twelve".