1221372262420 has 24 divisors (see below), whose sum is σ = 2567853840384. Its totient is φ = 487982792736.

The previous prime is 1221372262399. The next prime is 1221372262421. The reversal of 1221372262420 is 242622731221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221372262421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35364324 + ... + 35398843.

It is an arithmetic number, because the mean of its divisors is an integer number (106993910016).

Almost surely, 2^{1221372262420} is an apocalyptic number.

1221372262420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221372262420 is an abundant number, since it is smaller than the sum of its proper divisors (1346481577964).

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

1221372262420 is a wasteful number, since it uses less digits than its factorization.

1221372262420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70764039 (or 70764037 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 34.

Adding to 1221372262420 its reverse (242622731221), we get a palindrome (1463994993641).

The spelling of 1221372262420 in words is "one trillion, two hundred twenty-one billion, three hundred seventy-two million, two hundred sixty-two thousand, four hundred twenty".