421020423443 has 4 divisors (see below), whose sum is σ = 422070350088. Its totient is φ = 419970496800.

The previous prime is 421020423433. The next prime is 421020423493. The reversal of 421020423443 is 344324020124.

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 421020423443 - 2³⁴ = 403840554259 is a prime.

It is a super-2 number, since 2×421020423443² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (421020423413) 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, 524962721 + ... + 524963522.

It is an arithmetic number, because the mean of its divisors is an integer number (105517587522).

Almost surely, 2^421020423443 is an apocalyptic number.

421020423443 is a deficient number, since it is larger than the sum of its proper divisors (1049926645).

421020423443 is a wasteful number, since it uses less digits than its factorization.

421020423443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1049926644.

The product of its (nonzero) digits is 18432, while the sum is 29.

Adding to 421020423443 its reverse (344324020124), we get a palindrome (765344443567).

The spelling of 421020423443 in words is "four hundred twenty-one billion, twenty million, four hundred twenty-three thousand, four hundred forty-three".