420575521 has 4 divisors (see below), whose sum is σ = 421292592. Its totient is φ = 419858452.

The previous prime is 420575513. The next prime is 420575537. The reversal of 420575521 is 125575024.

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 a cyclic number.

It is not a de Polignac number, because 420575521 - 2³ = 420575513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (420575821) 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, 357655 + ... + 358828.

It is an arithmetic number, because the mean of its divisors is an integer number (105323148).

Almost surely, 2^420575521 is an apocalyptic number.

It is an amenable number.

420575521 is a deficient number, since it is larger than the sum of its proper divisors (717071).

420575521 is an equidigital number, since it uses as much as digits as its factorization.

420575521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 717070.

The product of its (nonzero) digits is 14000, while the sum is 31.

The square root of 420575521 is about 20507.9379997112. The cubic root of 420575521 is about 749.2291463547.

The spelling of 420575521 in words is "four hundred twenty million, five hundred seventy-five thousand, five hundred twenty-one".