420020987 has 2 divisors, whose sum is σ = 420020988. Its totient is φ = 420020986.

The previous prime is 420020983. The next prime is 420021029. The reversal of 420020987 is 789020024.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 420020987 - 2² = 420020983 is a prime.

It is not a weakly prime, because it can be changed into another prime (420020983) 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, 210010493 + 210010494.

It is an arithmetic number, because the mean of its divisors is an integer number (210010494).

Almost surely, 2^420020987 is an apocalyptic number.

420020987 is a deficient number, since it is larger than the sum of its proper divisors (1).

420020987 is an equidigital number, since it uses as much as digits as its factorization.

420020987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 420020987 is about 20494.4135558937. The cubic root of 420020987 is about 748.8997122415.

The spelling of 420020987 in words is "four hundred twenty million, twenty thousand, nine hundred eighty-seven".