26223291978 has 96 divisors (see below), whose sum is σ = 60087638016. Its totient is φ = 7582813056.

The previous prime is 26223291973. The next prime is 26223291989. The reversal of 26223291978 is 87919232262.

It is a super-2 number, since 2×26223291978² (a number of 22 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 26223291978.

It is not an unprimeable number, because it can be changed into a prime (26223291973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3572400 + ... + 3579732.

It is an arithmetic number, because the mean of its divisors is an integer number (625912896).

Almost surely, 2^26223291978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 26223291978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30043819008).

26223291978 is an abundant number, since it is smaller than the sum of its proper divisors (33864346038).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

26223291978 is a wasteful number, since it uses less digits than its factorization.

26223291978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7516 (or 7497 counting only the distinct ones).

The product of its digits is 1306368, while the sum is 51.

The spelling of 26223291978 in words is "twenty-six billion, two hundred twenty-three million, two hundred ninety-one thousand, nine hundred seventy-eight".