1227778456789 has 4 divisors (see below), whose sum is σ = 1228897672524. Its totient is φ = 1226659241056.

The previous prime is 1227778456777. The next prime is 1227778456799. The reversal of 1227778456789 is 9876548777221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 934682904100 + 293095552689 = 966790^2 + 541383^2 .

It is a cyclic number.

It is not a de Polignac number, because 1227778456789 - 2¹³ = 1227778448597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1227778456799) 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, 559606222 + ... + 559608415.

It is an arithmetic number, because the mean of its divisors is an integer number (307224418131).

Almost surely, 2^{1227778456789} is an apocalyptic number.

It is an amenable number.

1227778456789 is a deficient number, since it is larger than the sum of its proper divisors (1119215735).

1227778456789 is a wasteful number, since it uses less digits than its factorization.

1227778456789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1119215734.

The product of its digits is 663828480, while the sum is 73.

The spelling of 1227778456789 in words is "one trillion, two hundred twenty-seven billion, seven hundred seventy-eight million, four hundred fifty-six thousand, seven hundred eighty-nine".