420100861 has 2 divisors, whose sum is σ = 420100862. Its totient is φ = 420100860.

The previous prime is 420100859. The next prime is 420100903. The reversal of 420100861 is 168001024.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 246019225 + 174081636 = 15685^2 + 13194^2 .

It is a cyclic number.

It is not a de Polignac number, because 420100861 - 2¹ = 420100859 is a prime.

Together with 420100859, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420100831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210050430 + 210050431.

It is an arithmetic number, because the mean of its divisors is an integer number (210050431).

Almost surely, 2^420100861 is an apocalyptic number.

It is an amenable number.

420100861 is a deficient number, since it is larger than the sum of its proper divisors (1).

420100861 is an equidigital number, since it uses as much as digits as its factorization.

420100861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 420100861 is about 20496.3621406336. The cubic root of 420100861 is about 748.9471811586.

Adding to 420100861 its reverse (168001024), we get a palindrome (588101885).

The spelling of 420100861 in words is "four hundred twenty million, one hundred thousand, eight hundred sixty-one".