421423416021 has 4 divisors (see below), whose sum is σ = 561897888032. Its totient is φ = 280948944012.

The previous prime is 421423415927. The next prime is 421423416047. The reversal of 421423416021 is 120614324124.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 421423416021 - 2²¹ = 421421318869 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 421423416021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421423412021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70237236001 + ... + 70237236006.

It is an arithmetic number, because the mean of its divisors is an integer number (140474472008).

Almost surely, 2^421423416021 is an apocalyptic number.

It is an amenable number.

421423416021 is a deficient number, since it is larger than the sum of its proper divisors (140474472011).

421423416021 is a wasteful number, since it uses less digits than its factorization.

421423416021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140474472010.

The product of its (nonzero) digits is 9216, while the sum is 30.

The spelling of 421423416021 in words is "four hundred twenty-one billion, four hundred twenty-three million, four hundred sixteen thousand, twenty-one".