121756020408 has 96 divisors (see below), whose sum is σ = 360179164800. Its totient is φ = 36850075200.

The previous prime is 121756020401. The next prime is 121756020409. The reversal of 121756020408 is 804020657121.

121756020408 is a `hidden beast` number, since 1 + 2 + 1 + 7 + 5 + 602 + 0 + 40 + 8 = 666.

121756020408 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121756020401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 547533 + ... + 737091.

It is an arithmetic number, because the mean of its divisors is an integer number (3751866300).

Almost surely, 2^121756020408 is an apocalyptic number.

121756020408 is a gapful number since it is divisible by the number (18) 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 121756020408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180089582400).

121756020408 is an abundant number, since it is smaller than the sum of its proper divisors (238423144392).

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

121756020408 is a wasteful number, since it uses less digits than its factorization.

121756020408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190393 (or 190386 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

Adding to 121756020408 its reverse (804020657121), we get a palindrome (925776677529).

The spelling of 121756020408 in words is "one hundred twenty-one billion, seven hundred fifty-six million, twenty thousand, four hundred eight".