1861191693686 has 16 divisors (see below), whose sum is σ = 3006565708608. Its totient is φ = 859004328000.

The previous prime is 1861191693623. The next prime is 1861191693749. The reversal of 1861191693686 is 6863961911681.

It is an interprime number because it is at equal distance from previous prime (1861191693623) and next prime (1861191693749).

It is a super-2 number, since 2×1861191693686² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4022546 + ... + 4461306.

It is an arithmetic number, because the mean of its divisors is an integer number (187910356788).

Almost surely, 2^{1861191693686} is an apocalyptic number.

1861191693686 is a deficient number, since it is larger than the sum of its proper divisors (1145374014922).

1861191693686 is a wasteful number, since it uses less digits than its factorization.

1861191693686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 601927.

The product of its digits is 20155392, while the sum is 65.

The spelling of 1861191693686 in words is "one trillion, eight hundred sixty-one billion, one hundred ninety-one million, six hundred ninety-three thousand, six hundred eighty-six".