421103561 has 4 divisors (see below), whose sum is σ = 424318224. Its totient is φ = 417888900.

The previous prime is 421103539. The next prime is 421103563. The reversal of 421103561 is 165301124.

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 421103561 - 2²² = 416909257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (421103563) 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, 1607135 + ... + 1607396.

It is an arithmetic number, because the mean of its divisors is an integer number (106079556).

Almost surely, 2^421103561 is an apocalyptic number.

It is an amenable number.

421103561 is a deficient number, since it is larger than the sum of its proper divisors (3214663).

421103561 is a wasteful number, since it uses less digits than its factorization.

421103561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3214662.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 421103561 is about 20520.8080006612. The cubic root of 421103561 is about 749.5425720326.

Adding to 421103561 its reverse (165301124), we get a palindrome (586404685).

The spelling of 421103561 in words is "four hundred twenty-one million, one hundred three thousand, five hundred sixty-one".