420404261 has 2 divisors, whose sum is σ = 420404262. Its totient is φ = 420404260.

The previous prime is 420404251. The next prime is 420404269. The reversal of 420404261 is 162404024.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 387341761 + 33062500 = 19681^2 + 5750^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-420404261 is a prime.

It is a super-2 number, since 2×420404261² = 353479485333912242, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420404269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210202130 + 210202131.

It is an arithmetic number, because the mean of its divisors is an integer number (210202131).

Almost surely, 2^420404261 is an apocalyptic number.

It is an amenable number.

420404261 is a deficient number, since it is larger than the sum of its proper divisors (1).

420404261 is an equidigital number, since it uses as much as digits as its factorization.

420404261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 23.

The square root of 420404261 is about 20503.7621182065. The cubic root of 420404261 is about 749.1274361999.

Adding to 420404261 its reverse (162404024), we get a palindrome (582808285).

The spelling of 420404261 in words is "four hundred twenty million, four hundred four thousand, two hundred sixty-one".