1966451139887 has 8 divisors (see below), whose sum is σ = 2117732991360. Its totient is φ = 1815171628320.

The previous prime is 1966451139869. The next prime is 1966451139907. The reversal of 1966451139887 is 7889311546691.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1966451139887 - 2¹⁰ = 1966451138863 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1966451139827) 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, 1413314 + ... + 2435232.

It is an arithmetic number, because the mean of its divisors is an integer number (264716623920).

Almost surely, 2^{1966451139887} is an apocalyptic number.

1966451139887 is a deficient number, since it is larger than the sum of its proper divisors (151281851473).

1966451139887 is a wasteful number, since it uses less digits than its factorization.

1966451139887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1169953.

The product of its digits is 78382080, while the sum is 68.

The spelling of 1966451139887 in words is "one trillion, nine hundred sixty-six billion, four hundred fifty-one million, one hundred thirty-nine thousand, eight hundred eighty-seven".