121220774640 has 480 divisors, whose sum is σ = 487374788160. Its totient is φ = 27612555264.

The previous prime is 121220774629. The next prime is 121220774681. The reversal of 121220774640 is 46477022121.

121220774640 is a `hidden beast` number, since 1 + 2 + 1 + 2 + 2 + 0 + 7 + 7 + 4 + 640 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 121220774595 and 121220774604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 33549474 + ... + 33553086.

It is an arithmetic number, because the mean of its divisors is an integer number (1015364142).

Almost surely, 2^121220774640 is an apocalyptic number.

121220774640 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 121220774640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243687394080).

121220774640 is an abundant number, since it is smaller than the sum of its proper divisors (366154013520).

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

121220774640 is a wasteful number, since it uses less digits than its factorization.

121220774640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3966 (or 3947 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

Adding to 121220774640 its reverse (46477022121), we get a palindrome (167697796761).

The spelling of 121220774640 in words is "one hundred twenty-one billion, two hundred twenty million, seven hundred seventy-four thousand, six hundred forty".