420440431 has 4 divisors (see below), whose sum is σ = 427566600. Its totient is φ = 413314264.

The previous prime is 420440429. The next prime is 420440441. The reversal of 420440431 is 134044024.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 420440431 - 2¹ = 420440429 is a prime.

It is a super-2 number, since 2×420440431² = 353540312038931522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (420440411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3562996 + ... + 3563113.

It is an arithmetic number, because the mean of its divisors is an integer number (106891650).

Almost surely, 2^420440431 is an apocalyptic number.

420440431 is a deficient number, since it is larger than the sum of its proper divisors (7126169).

420440431 is an equidigital number, since it uses as much as digits as its factorization.

420440431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7126168.

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 420440431 is about 20504.6441324886. The cubic root of 420440431 is about 749.1489196186.

Adding to 420440431 its reverse (134044024), we get a palindrome (554484455).

The spelling of 420440431 in words is "four hundred twenty million, four hundred forty thousand, four hundred thirty-one".