421021123 has 2 divisors, whose sum is σ = 421021124. Its totient is φ = 421021122.

The previous prime is 421021121. The next prime is 421021157. The reversal of 421021123 is 321120124.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 421021123 - 2¹ = 421021121 is a prime.

It is a super-2 number, since 2×421021123² = 354517572024362258, which contains 22 as substring.

Together with 421021121, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 421021097 and 421021106.

It is not a weakly prime, because it can be changed into another prime (421021121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210510561 + 210510562.

It is an arithmetic number, because the mean of its divisors is an integer number (210510562).

Almost surely, 2^421021123 is an apocalyptic number.

421021123 is a deficient number, since it is larger than the sum of its proper divisors (1).

421021123 is an equidigital number, since it uses as much as digits as its factorization.

421021123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 421021123 is about 20518.7992582412. The cubic root of 421021123 is about 749.4936570475.

Adding to 421021123 its reverse (321120124), we get a palindrome (742141247).

Subtracting from 421021123 its reverse (321120124), we obtain a palindrome (99900999).

The spelling of 421021123 in words is "four hundred twenty-one million, twenty-one thousand, one hundred twenty-three".