78221012188 has 12 divisors (see below), whose sum is σ = 149331023352. Its totient is φ = 35555005520.

The previous prime is 78221012183. The next prime is 78221012197. The reversal of 78221012188 is 88121012287.

It is a super-2 number, since 2×78221012188² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78221012188.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78221012183) 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, 888875095 + ... + 888875182.

It is an arithmetic number, because the mean of its divisors is an integer number (12444251946).

Almost surely, 2^78221012188 is an apocalyptic number.

It is an amenable number.

78221012188 is a deficient number, since it is larger than the sum of its proper divisors (71110011164).

78221012188 is a wasteful number, since it uses less digits than its factorization.

78221012188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1777750292 (or 1777750290 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 40.

Subtracting 78221012188 from its reverse (88121012287), we obtain a palindrome (9900000099).

The spelling of 78221012188 in words is "seventy-eight billion, two hundred twenty-one million, twelve thousand, one hundred eighty-eight".