26431397 has 4 divisors (see below), whose sum is σ = 26693196. Its totient is φ = 26169600.

The previous prime is 26431387. The next prime is 26431403. The reversal of 26431397 is 79313462.

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 25867396 + 564001 = 5086^2 + 751^2 .

It is a cyclic number.

It is not a de Polignac number, because 26431397 - 2⁴ = 26431381 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 (26431387) 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, 130748 + ... + 130949.

It is an arithmetic number, because the mean of its divisors is an integer number (6673299).

Almost surely, 2^26431397 is an apocalyptic number.

It is an amenable number.

26431397 is a deficient number, since it is larger than the sum of its proper divisors (261799).

26431397 is a wasteful number, since it uses less digits than its factorization.

26431397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261798.

The product of its digits is 27216, while the sum is 35.

The square root of 26431397 is about 5141.1474400176. The cubic root of 26431397 is about 297.8791043019.

The spelling of 26431397 in words is "twenty-six million, four hundred thirty-one thousand, three hundred ninety-seven".