121211657743 has 16 divisors (see below), whose sum is σ = 135858481920. Its totient is φ = 107207942400.

The previous prime is 121211657741. The next prime is 121211657761. The reversal of 121211657743 is 347756112121.

It is a cyclic number.

It is not a de Polignac number, because 121211657743 - 2¹ = 121211657741 is a prime.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 121211657696 and 121211657705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121211657741) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 899763 + ... + 1025668.

It is an arithmetic number, because the mean of its divisors is an integer number (8491155120).

Almost surely, 2^121211657743 is an apocalyptic number.

121211657743 is a deficient number, since it is larger than the sum of its proper divisors (14646824177).

121211657743 is a wasteful number, since it uses less digits than its factorization.

121211657743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1925598.

The product of its digits is 70560, while the sum is 40.

Adding to 121211657743 its reverse (347756112121), we get a palindrome (468967769864).

The spelling of 121211657743 in words is "one hundred twenty-one billion, two hundred eleven million, six hundred fifty-seven thousand, seven hundred forty-three".