101212121987 has 4 divisors (see below), whose sum is σ = 103121784720. Its totient is φ = 99302459256.

The previous prime is 101212121977. The next prime is 101212122041. The reversal of 101212121987 is 789121212101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789121212101 = 31 ⋅25455522971.

It is a cyclic number.

It is not a de Polignac number, because 101212121987 - 2¹⁰ = 101212120963 is a prime.

It is a super-2 number, since 2×101212121987² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (101212121947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 954831287 + ... + 954831392.

It is an arithmetic number, because the mean of its divisors is an integer number (25780446180).

Almost surely, 2^101212121987 is an apocalyptic number.

101212121987 is a deficient number, since it is larger than the sum of its proper divisors (1909662733).

101212121987 is an equidigital number, since it uses as much as digits as its factorization.

101212121987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1909662732.

The product of its (nonzero) digits is 4032, while the sum is 35.

The spelling of 101212121987 in words is "one hundred one billion, two hundred twelve million, one hundred twenty-one thousand, nine hundred eighty-seven".