121557707511 has 8 divisors (see below), whose sum is σ = 171610881264. Its totient is φ = 76271502720.

The previous prime is 121557707497. The next prime is 121557707549. The reversal of 121557707511 is 115707755121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121557707511 - 2¹⁴ = 121557691127 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121557707911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1191742180 + ... + 1191742281.

It is an arithmetic number, because the mean of its divisors is an integer number (21451360158).

Almost surely, 2^121557707511 is an apocalyptic number.

121557707511 is a deficient number, since it is larger than the sum of its proper divisors (50053173753).

121557707511 is a wasteful number, since it uses less digits than its factorization.

121557707511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2383484481.

The product of its (nonzero) digits is 85750, while the sum is 42.

The spelling of 121557707511 in words is "one hundred twenty-one billion, five hundred fifty-seven million, seven hundred seven thousand, five hundred eleven".