1221025252000 has 96 divisors (see below), whose sum is σ = 3013161999120. Its totient is φ = 486276940800.

The previous prime is 1221025251989. The next prime is 1221025252033. The reversal of 1221025252000 is 2525201221.

It can be written as a sum of positive squares in 8 ways, for example, as 288278791056 + 932746460944 = 536916^2 + 965788^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 249502 + ... + 1582498.

Almost surely, 2^{1221025252000} is an apocalyptic number.

1221025252000 is a gapful number since it is divisible by the number (10) 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 1221025252000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1506580999560).

1221025252000 is an abundant number, since it is smaller than the sum of its proper divisors (1792136747120).

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

1221025252000 is a wasteful number, since it uses less digits than its factorization.

1221025252000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1333251 (or 1333233 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

It can be divided in two parts, 12 and 21025252000, that added together give a palindrome (21025252012).

The spelling of 1221025252000 in words is "one trillion, two hundred twenty-one billion, twenty-five million, two hundred fifty-two thousand".