121289007840 has 1536 divisors, whose sum is σ = 561842749440. Its totient is φ = 21145190400.

The previous prime is 121289007839. The next prime is 121289007877. The reversal of 121289007840 is 48700982121.

It is a super-2 number, since 2×121289007840² (a number of 23 digits) contains 22 as substring.

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 = 121289007792 and 121289007801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 253212721 + ... + 253213199.

It is an arithmetic number, because the mean of its divisors is an integer number (365783040).

Almost surely, 2^121289007840 is an apocalyptic number.

121289007840 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 121289007840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (280921374720).

121289007840 is an abundant number, since it is smaller than the sum of its proper divisors (440553741600).

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

121289007840 is a wasteful number, since it uses less digits than its factorization.

121289007840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576 (or 568 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 42.

Adding to 121289007840 its reverse (48700982121), we get a palindrome (169989989961).

The spelling of 121289007840 in words is "one hundred twenty-one billion, two hundred eighty-nine million, seven thousand, eight hundred forty".