121551220240000 has 80 divisors (see below), whose sum is σ = 302594166035370. Its totient is φ = 48620488064000.

The previous prime is 121551220239979. The next prime is 121551220240033. The reversal of 121551220240000 is 42022155121.

It can be written as a sum of positive squares in 5 ways, for example, as 12665000499264 + 108886219740736 = 3558792^2 + 10434856^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (25).

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 759615127 + ... + 759775126.

Almost surely, 2^{121551220240000} is an apocalyptic number.

121551220240000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121551220240000 is an abundant number, since it is smaller than the sum of its proper divisors (181042945795370).

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

121551220240000 is an frugal number, since it uses more digits than its factorization.

121551220240000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1519390287 (or 1519390260 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

Adding to 121551220240000 its reverse (42022155121), we get a palindrome (121593242395121).

The spelling of 121551220240000 in words is "one hundred twenty-one trillion, five hundred fifty-one billion, two hundred twenty million, two hundred forty thousand".