420313521 has 4 divisors (see below), whose sum is σ = 560418032. Its totient is φ = 280209012.

The previous prime is 420313499. The next prime is 420313549. The reversal of 420313521 is 125313024.

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 420313521 - 2¹¹ = 420311473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (420313561) 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, 70052251 + ... + 70052256.

It is an arithmetic number, because the mean of its divisors is an integer number (140104508).

Almost surely, 2^420313521 is an apocalyptic number.

It is an amenable number.

420313521 is a deficient number, since it is larger than the sum of its proper divisors (140104511).

420313521 is a wasteful number, since it uses less digits than its factorization.

420313521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140104510.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 420313521 is about 20501.5492341433. The cubic root of 420313521 is about 749.0735351328.

Adding to 420313521 its reverse (125313024), we get a palindrome (545626545).

The spelling of 420313521 in words is "four hundred twenty million, three hundred thirteen thousand, five hundred twenty-one".