1657650091666 has 8 divisors (see below), whose sum is σ = 2486485436220. Its totient is φ = 828821612928.

The previous prime is 1657650091663. The next prime is 1657650091697. The reversal of 1657650091666 is 6661900567561.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1635188775025 + 22461316641 = 1278745^2 + 149871^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1657650091666.

It is not an unprimeable number, because it can be changed into a prime (1657650091661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1063131 + ... + 2108446.

Almost surely, 2^{1657650091666} is an apocalyptic number.

1657650091666 is a deficient number, since it is larger than the sum of its proper divisors (828835344554).

1657650091666 is a wasteful number, since it uses less digits than its factorization.

1657650091666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3432908.

The product of its (nonzero) digits is 12247200, while the sum is 58.

The spelling of 1657650091666 in words is "one trillion, six hundred fifty-seven billion, six hundred fifty million, ninety-one thousand, six hundred sixty-six".