1909666189961 has 8 divisors (see below), whose sum is σ = 1960981909920. Its totient is φ = 1858664328192.

The previous prime is 1909666189943. The next prime is 1909666189993. The reversal of 1909666189961 is 1699816669091.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1909666189961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1909666189661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78452216 + ... + 78476553.

It is an arithmetic number, because the mean of its divisors is an integer number (245122738740).

Almost surely, 2^{1909666189961} is an apocalyptic number.

It is an amenable number.

1909666189961 is a deficient number, since it is larger than the sum of its proper divisors (51315719959).

1909666189961 is a wasteful number, since it uses less digits than its factorization.

1909666189961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156929095.

The product of its (nonzero) digits is 68024448, while the sum is 71.

The spelling of 1909666189961 in words is "one trillion, nine hundred nine billion, six hundred sixty-six million, one hundred eighty-nine thousand, nine hundred sixty-one".