421111111 has 4 divisors (see below), whose sum is σ = 424837872. Its totient is φ = 417384352.

The previous prime is 421111091. The next prime is 421111151. The reversal of 421111111 is 111111124.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 421111111 - 2¹³ = 421102919 is a prime.

It is a Duffinian number.

421111111 is a modest number, since divided by 11111 gives 4211 as remainder.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 421111091 and 421111100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (421111151) 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, 1863211 + ... + 1863436.

It is an arithmetic number, because the mean of its divisors is an integer number (106209468).

Almost surely, 2^421111111 is an apocalyptic number.

421111111 is a deficient number, since it is larger than the sum of its proper divisors (3726761).

421111111 is a wasteful number, since it uses less digits than its factorization.

421111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3726760.

The product of its digits is 8, while the sum is 13.

The square root of 421111111 is about 20520.9919594546. The cubic root of 421111111 is about 749.5470515424.

Adding to 421111111 its sum of digits (13), we get a palindrome (421111124).

Adding to 421111111 its reverse (111111124), we get a palindrome (532222235).

The spelling of 421111111 in words is "four hundred twenty-one million, one hundred eleven thousand, one hundred eleven".