21111143987 has 8 divisors (see below), whose sum is σ = 21160986000. Its totient is φ = 21061361664.

The previous prime is 21111143981. The next prime is 21111144011. The reversal of 21111143987 is 78934111112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21111143987 - 2⁴ = 21111143971 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21111143987.

It is not an unprimeable number, because it can be changed into a prime (21111143981) 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 7 ways as a sum of consecutive naturals, for example, 737264 + ... + 765362.

It is an arithmetic number, because the mean of its divisors is an integer number (2645123250).

Almost surely, 2^21111143987 is an apocalyptic number.

21111143987 is a deficient number, since it is larger than the sum of its proper divisors (49842013).

21111143987 is an equidigital number, since it uses as much as digits as its factorization.

21111143987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29845.

The product of its digits is 12096, while the sum is 38.

The spelling of 21111143987 in words is "twenty-one billion, one hundred eleven million, one hundred forty-three thousand, nine hundred eighty-seven".