220231987 has 2 divisors, whose sum is σ = 220231988. Its totient is φ = 220231986.

The previous prime is 220231981. The next prime is 220231997. The reversal of 220231987 is 789132022.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 220231987 - 2¹¹ = 220229939 is a prime.

It is not a weakly prime, because it can be changed into another prime (220231981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110115993 + 110115994.

It is an arithmetic number, because the mean of its divisors is an integer number (110115994).

Almost surely, 2^220231987 is an apocalyptic number.

220231987 is a deficient number, since it is larger than the sum of its proper divisors (1).

220231987 is an equidigital number, since it uses as much as digits as its factorization.

220231987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 220231987 is about 14840.2151938575. The cubic root of 220231987 is about 603.8931902926.

The spelling of 220231987 in words is "two hundred twenty million, two hundred thirty-one thousand, nine hundred eighty-seven".