421205971 has 2 divisors, whose sum is σ = 421205972. Its totient is φ = 421205970.

The previous prime is 421205951. The next prime is 421206017. The reversal of 421205971 is 179502124.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 421205971 - 2⁹ = 421205459 is a prime.

It is not a weakly prime, because it can be changed into another prime (421205951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210602985 + 210602986.

It is an arithmetic number, because the mean of its divisors is an integer number (210602986).

Almost surely, 2^421205971 is an apocalyptic number.

421205971 is a deficient number, since it is larger than the sum of its proper divisors (1).

421205971 is an equidigital number, since it uses as much as digits as its factorization.

421205971 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5040, while the sum is 31.

The square root of 421205971 is about 20523.3031210865. The cubic root of 421205971 is about 749.6033286098.

The spelling of 421205971 in words is "four hundred twenty-one million, two hundred five thousand, nine hundred seventy-one".