10121987 has 4 divisors (see below), whose sum is σ = 10717416. Its totient is φ = 9526560.

The previous prime is 10121963. The next prime is 10121999. The reversal of 10121987 is 78912101.

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

It is a cyclic number.

It is not a de Polignac number, because 10121987 - 2⁸ = 10121731 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (10121687) 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, 297689 + ... + 297722.

It is an arithmetic number, because the mean of its divisors is an integer number (2679354).

Almost surely, 2^10121987 is an apocalyptic number.

10121987 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

10121987 is a deficient number, since it is larger than the sum of its proper divisors (595429).

10121987 is an equidigital number, since it uses as much as digits as its factorization.

10121987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595428.

The product of its (nonzero) digits is 1008, while the sum is 29.

The square root of 10121987 is about 3181.5070328384. The cubic root of 10121987 is about 216.3159741680.

The spelling of 10121987 in words is "ten million, one hundred twenty-one thousand, nine hundred eighty-seven".