121556751705 has 64 divisors (see below), whose sum is σ = 217307485440. Its totient is φ = 64469260800.

The previous prime is 121556751637. The next prime is 121556751739. The reversal of 121556751705 is 507157655121.

121556751705 is a `hidden beast` number, since 1 + 2 + 15 + 567 + 5 + 1 + 70 + 5 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-121556751705 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 20519874 + ... + 20525796.

It is an arithmetic number, because the mean of its divisors is an integer number (3395429460).

Almost surely, 2^121556751705 is an apocalyptic number.

121556751705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121556751705 is a deficient number, since it is larger than the sum of its proper divisors (95750733735).

121556751705 is a wasteful number, since it uses less digits than its factorization.

121556751705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6759 (or 6753 counting only the distinct ones).

The product of its (nonzero) digits is 367500, while the sum is 45.

The spelling of 121556751705 in words is "one hundred twenty-one billion, five hundred fifty-six million, seven hundred fifty-one thousand, seven hundred five".