100987681 has 2 divisors, whose sum is σ = 100987682. Its totient is φ = 100987680.

The previous prime is 100987673. The next prime is 100987699. The reversal of 100987681 is 186789001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97693456 + 3294225 = 9884^2 + 1815^2 .

It is a cyclic number.

It is not a de Polignac number, because 100987681 - 2³ = 100987673 is a prime.

It is a super-2 number, since 2×100987681² = 20397023427515522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (100987661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50493840 + 50493841.

It is an arithmetic number, because the mean of its divisors is an integer number (50493841).

Almost surely, 2^100987681 is an apocalyptic number.

It is an amenable number.

100987681 is a deficient number, since it is larger than the sum of its proper divisors (1).

100987681 is an equidigital number, since it uses as much as digits as its factorization.

100987681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 40.

The square root of 100987681 is about 10049.2627092738. The cubic root of 100987681 is about 465.6820161161.

The spelling of 100987681 in words is "one hundred million, nine hundred eighty-seven thousand, six hundred eighty-one".