2187487686981 has 32 divisors (see below), whose sum is σ = 3106464628608. Its totient is φ = 1364433674240.

The previous prime is 2187487686977. The next prime is 2187487686983. The reversal of 2187487686981 is 1896867847812.

It is a cyclic number.

It is not a de Polignac number, because 2187487686981 - 2² = 2187487686977 is a prime.

It is a super-2 number, since 2×2187487686981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2187487686983) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 128463190 + ... + 128480216.

It is an arithmetic number, because the mean of its divisors is an integer number (97077019644).

Almost surely, 2^{2187487686981} is an apocalyptic number.

It is an amenable number.

2187487686981 is a deficient number, since it is larger than the sum of its proper divisors (918976941627).

2187487686981 is a wasteful number, since it uses less digits than its factorization.

2187487686981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31781.

The product of its digits is 520224768, while the sum is 75.

The spelling of 2187487686981 in words is "two trillion, one hundred eighty-seven billion, four hundred eighty-seven million, six hundred eighty-six thousand, nine hundred eighty-one".