1221003421 has 8 divisors (see below), whose sum is σ = 1332851904. Its totient is φ = 1109296320.

The previous prime is 1221003419. The next prime is 1221003463. The reversal of 1221003421 is 1243001221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1221003421 - 2¹ = 1221003419 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221003395 and 1221003404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221003521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16860 + ... + 52213.

It is an arithmetic number, because the mean of its divisors is an integer number (166606488).

Almost surely, 2^1221003421 is an apocalyptic number.

1221003421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221003421 is a deficient number, since it is larger than the sum of its proper divisors (111848483).

1221003421 is a wasteful number, since it uses less digits than its factorization.

1221003421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70691.

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

The square root of 1221003421 is about 34942.8593706926. The cubic root of 1221003421 is about 1068.8225966395.

Adding to 1221003421 its reverse (1243001221), we get a palindrome (2464004642).

It can be divided in two parts, 122100 and 3421, that added together give a palindrome (125521).

The spelling of 1221003421 in words is "one billion, two hundred twenty-one million, three thousand, four hundred twenty-one".