26640009 has 40 divisors (see below), whose sum is σ = 44953920. Its totient is φ = 15573600.

The previous prime is 26640001. The next prime is 26640013. The reversal of 26640009 is 90004662.

It is not a de Polignac number, because 26640009 - 2³ = 26640001 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26640001) 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, 25324 + ... + 26354.

It is an arithmetic number, because the mean of its divisors is an integer number (1123848).

Almost surely, 2^26640009 is an apocalyptic number.

26640009 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

26640009 is a deficient number, since it is larger than the sum of its proper divisors (18313911).

26640009 is a wasteful number, since it uses less digits than its factorization.

26640009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1083 (or 1074 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 26640009 is about 5161.3960320828. The cubic root of 26640009 is about 298.6607300839.

The spelling of 26640009 in words is "twenty-six million, six hundred forty thousand, nine".