221421322987 has 2 divisors, whose sum is σ = 221421322988. Its totient is φ = 221421322986.

The previous prime is 221421322963. The next prime is 221421323029. The reversal of 221421322987 is 789223124122.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221421322987 - 2¹⁵ = 221421290219 is a prime.

It is not a weakly prime, because it can be changed into another prime (221421322907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110710661493 + 110710661494.

It is an arithmetic number, because the mean of its divisors is an integer number (110710661494).

Almost surely, 2^221421322987 is an apocalyptic number.

221421322987 is a deficient number, since it is larger than the sum of its proper divisors (1).

221421322987 is an equidigital number, since it uses as much as digits as its factorization.

221421322987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 193536, while the sum is 43.

The spelling of 221421322987 in words is "two hundred twenty-one billion, four hundred twenty-one million, three hundred twenty-two thousand, nine hundred eighty-seven".