1661107010649 has 16 divisors (see below), whose sum is σ = 2468518159680. Its totient is φ = 987407262720.

The previous prime is 1661107010603. The next prime is 1661107010657. The reversal of 1661107010649 is 9460107011661.

It is not a de Polignac number, because 1661107010649 - 2¹¹ = 1661107008601 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1661107010649.

It is not an unprimeable number, because it can be changed into a prime (1661107010669) 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 15 ways as a sum of consecutive naturals, for example, 857123392 + ... + 857125329.

It is an arithmetic number, because the mean of its divisors is an integer number (154282384980).

Almost surely, 2^{1661107010649} is an apocalyptic number.

1661107010649 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1661107010649 is a deficient number, since it is larger than the sum of its proper divisors (807411149031).

1661107010649 is a wasteful number, since it uses less digits than its factorization.

1661107010649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1714248760.

The product of its (nonzero) digits is 54432, while the sum is 42.

The spelling of 1661107010649 in words is "one trillion, six hundred sixty-one billion, one hundred seven million, ten thousand, six hundred forty-nine".