78121677612187 has 16 divisors (see below), whose sum is σ = 85920554299392. Its totient is φ = 70439288562720.

The previous prime is 78121677612091. The next prime is 78121677612203.

78121677612187 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 78121677612187 - 2⁷ = 78121677612059 is a prime.

It is a super-2 number, since 2×78121677612187² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78121677612487) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3772008 + ... + 13056469.

It is an arithmetic number, because the mean of its divisors is an integer number (5370034643712).

Almost surely, 2^{78121677612187} is an apocalyptic number.

78121677612187 is a deficient number, since it is larger than the sum of its proper divisors (7798876687205).

78121677612187 is a wasteful number, since it uses less digits than its factorization.

78121677612187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16831938.

The product of its digits is 22127616, while the sum is 64.

The spelling of 78121677612187 in words is "seventy-eight trillion, one hundred twenty-one billion, six hundred seventy-seven million, six hundred twelve thousand, one hundred eighty-seven".