26431531217 has 24 divisors (see below), whose sum is σ = 32728797504. Its totient is φ = 20900752704.

The previous prime is 26431531183. The next prime is 26431531241. The reversal of 26431531217 is 71213513462.

It is not a de Polignac number, because 26431531217 - 2²⁶ = 26364422353 is a prime.

It is not an unprimeable number, because it can be changed into a prime (26431531267) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2423258 + ... + 2434140.

It is an arithmetic number, because the mean of its divisors is an integer number (1363699896).

Almost surely, 2^26431531217 is an apocalyptic number.

It is an amenable number.

26431531217 is a deficient number, since it is larger than the sum of its proper divisors (6297266287).

26431531217 is a wasteful number, since it uses less digits than its factorization.

26431531217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12969 (or 12956 counting only the distinct ones).

The product of its digits is 30240, while the sum is 35.

The spelling of 26431531217 in words is "twenty-six billion, four hundred thirty-one million, five hundred thirty-one thousand, two hundred seventeen".