26319978 has 80 divisors (see below), whose sum is σ = 65862720. Its totient is φ = 7807104.

The previous prime is 26319977. The next prime is 26319983. The reversal of 26319978 is 87991362.

26319978 is a `hidden beast` number, since 2 + 631 + 9 + 9 + 7 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (26319973) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 52075 + ... + 52577.

It is an arithmetic number, because the mean of its divisors is an integer number (823284).

Almost surely, 2^26319978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 26319978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32931360).

26319978 is an abundant number, since it is smaller than the sum of its proper divisors (39542742).

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

26319978 is a wasteful number, since it uses less digits than its factorization.

26319978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 553 (or 544 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 26319978 is about 5130.2999912286. The cubic root of 26319978 is about 297.4599545939.

The spelling of 26319978 in words is "twenty-six million, three hundred nineteen thousand, nine hundred seventy-eight".