100999987 has 4 divisors (see below), whose sum is σ = 110181816. Its totient is φ = 91818160.

The previous prime is 100999981. The next prime is 100999993. The reversal of 100999987 is 789999001.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (100999981) and next prime (100999993).

It is a cyclic number.

It is not a de Polignac number, because 100999987 - 2³ = 100999979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100999981) 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 in 3 ways as a sum of consecutive naturals, for example, 4590898 + ... + 4590919.

It is an arithmetic number, because the mean of its divisors is an integer number (27545454).

Almost surely, 2^100999987 is an apocalyptic number.

100999987 is a deficient number, since it is larger than the sum of its proper divisors (9181829).

100999987 is an equidigital number, since it uses as much as digits as its factorization.

100999987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9181828.

The product of its (nonzero) digits is 367416, while the sum is 52.

The square root of 100999987 is about 10049.8749743467. The cubic root of 100999987 is about 465.7009307998.

The spelling of 100999987 in words is "one hundred million, nine hundred ninety-nine thousand, nine hundred eighty-seven".