1221000134144 has 80 divisors (see below), whose sum is σ = 2793814505856. Its totient is φ = 522219264000.

The previous prime is 1221000134113. The next prime is 1221000134213. The reversal of 1221000134144 is 4414310001221.

It is a super-2 number, since 2×1221000134144² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1412819 + ... + 2106669.

Almost surely, 2^{1221000134144} is an apocalyptic number.

1221000134144 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221000134144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1396907252928).

1221000134144 is an abundant number, since it is smaller than the sum of its proper divisors (1572814371712).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221000134144 is an frugal number, since it uses more digits than its factorization.

1221000134144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 694367 (or 694351 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 23.

Adding to 1221000134144 its reverse (4414310001221), we get a palindrome (5635310135365).

The spelling of 1221000134144 in words is "one trillion, two hundred twenty-one billion, one hundred thirty-four thousand, one hundred forty-four".