1220176421 has 4 divisors (see below), whose sum is σ = 1262251500. Its totient is φ = 1178101344.

The previous prime is 1220176379. The next prime is 1220176457. The reversal of 1220176421 is 1246710221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1246710221 = 353 ⋅3531757.

It can be written as a sum of positive squares in 2 ways, for example, as 584430625 + 635745796 = 24175^2 + 25214^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220176421 - 2⁶ = 1220176357 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 (1220176481) 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, 21037496 + ... + 21037553.

It is an arithmetic number, because the mean of its divisors is an integer number (315562875).

Almost surely, 2^1220176421 is an apocalyptic number.

It is an amenable number.

1220176421 is a deficient number, since it is larger than the sum of its proper divisors (42075079).

1220176421 is an equidigital number, since it uses as much as digits as its factorization.

1220176421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42075078.

The product of its (nonzero) digits is 1344, while the sum is 26.

The square root of 1220176421 is about 34931.0237611210. The cubic root of 1220176421 is about 1068.5812334269.

Adding to 1220176421 its reverse (1246710221), we get a palindrome (2466886642).

The spelling of 1220176421 in words is "one billion, two hundred twenty million, one hundred seventy-six thousand, four hundred twenty-one".