21201200987 has 2 divisors, whose sum is σ = 21201200988. Its totient is φ = 21201200986.

The previous prime is 21201200971. The next prime is 21201201061. The reversal of 21201200987 is 78900210212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21201200987 - 2⁴ = 21201200971 is a prime.

It is not a weakly prime, because it can be changed into another prime (21201202987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600600493 + 10600600494.

It is an arithmetic number, because the mean of its divisors is an integer number (10600600494).

Almost surely, 2^21201200987 is an apocalyptic number.

21201200987 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201200987 is an equidigital number, since it uses as much as digits as its factorization.

21201200987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 32.

The spelling of 21201200987 in words is "twenty-one billion, two hundred one million, two hundred thousand, nine hundred eighty-seven".