121280857187 has 4 divisors (see below), whose sum is σ = 138606693936. Its totient is φ = 103955020440.

The previous prime is 121280857169. The next prime is 121280857277. The reversal of 121280857187 is 781758082121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 781758082121 = 19139 ⋅40846339.

It is a cyclic number.

It is not a de Polignac number, because 121280857187 - 2¹² = 121280853091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121280854187) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8662918364 + ... + 8662918377.

It is an arithmetic number, because the mean of its divisors is an integer number (34651673484).

Almost surely, 2^121280857187 is an apocalyptic number.

121280857187 is a deficient number, since it is larger than the sum of its proper divisors (17325836749).

121280857187 is an equidigital number, since it uses as much as digits as its factorization.

121280857187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17325836748.

The product of its (nonzero) digits is 501760, while the sum is 50.

The spelling of 121280857187 in words is "one hundred twenty-one billion, two hundred eighty million, eight hundred fifty-seven thousand, one hundred eighty-seven".