420401831 has 2 divisors, whose sum is σ = 420401832. Its totient is φ = 420401830.

The previous prime is 420401791. The next prime is 420401833. The reversal of 420401831 is 138104024.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 420401831 - 2¹⁰ = 420400807 is a prime.

It is a super-2 number, since 2×420401831² = 353475399016305122, which contains 22 as substring.

Together with 420401833, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 420401797 and 420401806.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (420401833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210200915 + 210200916.

It is an arithmetic number, because the mean of its divisors is an integer number (210200916).

Almost surely, 2^420401831 is an apocalyptic number.

420401831 is a deficient number, since it is larger than the sum of its proper divisors (1).

420401831 is an equidigital number, since it uses as much as digits as its factorization.

420401831 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 420401831 is about 20503.7028607030. The cubic root of 420401831 is about 749.1259928406.

Adding to 420401831 its reverse (138104024), we get a palindrome (558505855).

The spelling of 420401831 in words is "four hundred twenty million, four hundred one thousand, eight hundred thirty-one".