420110021 has 2 divisors, whose sum is σ = 420110022. Its totient is φ = 420110020.

The previous prime is 420110011. The next prime is 420110027. The reversal of 420110021 is 120011024.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 370562500 + 49547521 = 19250^2 + 7039^2 .

It is a cyclic number.

It is not a de Polignac number, because 420110021 - 2²⁶ = 353001157 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 420109984 and 420110011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420110027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210055010 + 210055011.

It is an arithmetic number, because the mean of its divisors is an integer number (210055011).

Almost surely, 2^420110021 is an apocalyptic number.

It is an amenable number.

420110021 is a deficient number, since it is larger than the sum of its proper divisors (1).

420110021 is an equidigital number, since it uses as much as digits as its factorization.

420110021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 420110021 is about 20496.5855937032. The cubic root of 420110021 is about 748.9526245389.

Adding to 420110021 its reverse (120011024), we get a palindrome (540121045).

The spelling of 420110021 in words is "four hundred twenty million, one hundred ten thousand, twenty-one".