421421807 has 2 divisors, whose sum is σ = 421421808. Its totient is φ = 421421806.

The previous prime is 421421783. The next prime is 421421813. The reversal of 421421807 is 708124124.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 421421807 - 2²⁶ = 354312943 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 421421807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (421421867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210710903 + 210710904.

It is an arithmetic number, because the mean of its divisors is an integer number (210710904).

Almost surely, 2^421421807 is an apocalyptic number.

421421807 is a deficient number, since it is larger than the sum of its proper divisors (1).

421421807 is an equidigital number, since it uses as much as digits as its factorization.

421421807 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3584, while the sum is 29.

The square root of 421421807 is about 20528.5607629955. The cubic root of 421421807 is about 749.7313449626.

The spelling of 421421807 in words is "four hundred twenty-one million, four hundred twenty-one thousand, eight hundred seven".