22222227777778 has 32 divisors (see below), whose sum is σ = 38906922797568. Its totient is φ = 9320904964800.

The previous prime is 22222227777767. The next prime is 22222227777779. The reversal of 22222227777778 is 87777772222222.

It is a happy number.

22222227777778 is a nontrivial binomial coefficient, being equal to C(6666668, 2).

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (22222227777779) 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, 22857148 + ... + 23809528.

It is an arithmetic number, because the mean of its divisors is an integer number (1215841337424).

Almost surely, 2^{22222227777778} is an apocalyptic number.

22222227777778 is the 6666667-th triangular number and also the 3333334-th hexagonal number.

22222227777778 is the 2222223-rd centered nonagonal number.

22222227777778 is a deficient number, since it is larger than the sum of its proper divisors (16684695019790).

22222227777778 is a wasteful number, since it uses less digits than its factorization.

22222227777778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 987898.

The product of its digits is 120472576, while the sum is 64.

It can be divided in two parts, 2222222 and 7777778, that added together give a 7-th power (10000000 = 10⁷).

The spelling of 22222227777778 in words is "twenty-two trillion, two hundred twenty-two billion, two hundred twenty-seven million, seven hundred seventy-seven thousand, seven hundred seventy-eight".