121984502640 has 640 divisors, whose sum is σ = 525266380800. Its totient is φ = 22589521920.

The previous prime is 121984502623. The next prime is 121984502641. The reversal of 121984502640 is 46205489121.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 121984502592 and 121984502601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121984502641) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 6958206 + ... + 6975714.

It is an arithmetic number, because the mean of its divisors is an integer number (820728720).

Almost surely, 2^121984502640 is an apocalyptic number.

121984502640 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 121984502640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (262633190400).

121984502640 is an abundant number, since it is smaller than the sum of its proper divisors (403281878160).

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

121984502640 is a wasteful number, since it uses less digits than its factorization.

121984502640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17585 (or 17579 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 42.

The spelling of 121984502640 in words is "one hundred twenty-one billion, nine hundred eighty-four million, five hundred two thousand, six hundred forty".