1231420421 has 32 divisors (see below), whose sum is σ = 1609132800. Its totient is φ = 933508800.

The previous prime is 1231420387. The next prime is 1231420499. The reversal of 1231420421 is 1240241321.

It is not a de Polignac number, because 1231420421 - 2²⁶ = 1164311557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1231420393 and 1231420402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231426421) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 135191 + ... + 144011.

It is an arithmetic number, because the mean of its divisors is an integer number (50285400).

Almost surely, 2^1231420421 is an apocalyptic number.

1231420421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1231420421 is a deficient number, since it is larger than the sum of its proper divisors (377712379).

1231420421 is an equidigital number, since it uses as much as digits as its factorization.

1231420421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8890 (or 8876 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 1231420421 is about 35091.6004337220. The cubic root of 1231420421 is about 1071.8535494250.

Adding to 1231420421 its reverse (1240241321), we get a palindrome (2471661742).

Subtracting 1231420421 from its reverse (1240241321), we obtain a square (8820900 = 2970²).

The spelling of 1231420421 in words is "one billion, two hundred thirty-one million, four hundred twenty thousand, four hundred twenty-one".