421560421 has 4 divisors (see below), whose sum is σ = 421693344. Its totient is φ = 421427500.

The previous prime is 421560409. The next prime is 421560439. The reversal of 421560421 is 124065124.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-421560421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421560221) 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, 61585 + ... + 68086.

It is an arithmetic number, because the mean of its divisors is an integer number (105423336).

Almost surely, 2^421560421 is an apocalyptic number.

It is an amenable number.

421560421 is a deficient number, since it is larger than the sum of its proper divisors (132923).

421560421 is a wasteful number, since it uses less digits than its factorization.

421560421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132922.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 421560421 is about 20531.9366110457. The cubic root of 421560421 is about 749.8135364605.

The spelling of 421560421 in words is "four hundred twenty-one million, five hundred sixty thousand, four hundred twenty-one".