21200111021987 has 8 divisors (see below), whose sum is σ = 21983242337040. Its totient is φ = 20420452573920.

The previous prime is 21200111021983. The next prime is 21200111022011. The reversal of 21200111021987 is 78912011100212.

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 21200111021987 - 2² = 21200111021983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21200111021983) 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, 868204313 + ... + 868228730.

It is an arithmetic number, because the mean of its divisors is an integer number (2747905292130).

Almost surely, 2^{21200111021987} is an apocalyptic number.

21200111021987 is a deficient number, since it is larger than the sum of its proper divisors (783131315053).

21200111021987 is a wasteful number, since it uses less digits than its factorization.

21200111021987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736433493.

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

The spelling of 21200111021987 in words is "twenty-one trillion, two hundred billion, one hundred eleven million, twenty-one thousand, nine hundred eighty-seven".