909640138 has 16 divisors (see below), whose sum is σ = 1503243360. Its totient is φ = 409378000.

The previous prime is 909640117. The next prime is 909640139. The reversal of 909640138 is 831046909.

It is a super-5 number, since 5×909640138⁵ (a number of 46 digits) contains 55555 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 909640138.

It is not an unprimeable number, because it can be changed into a prime (909640139) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 202468 + ... + 206911.

It is an arithmetic number, because the mean of its divisors is an integer number (93952710).

Almost surely, 2^909640138 is an apocalyptic number.

909640138 is a deficient number, since it is larger than the sum of its proper divisors (593603222).

909640138 is a wasteful number, since it uses less digits than its factorization.

909640138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409493.

The product of its (nonzero) digits is 46656, while the sum is 40.

The square root of 909640138 is about 30160.2410136259. The cubic root of 909640138 is about 968.9243533954.

The spelling of 909640138 in words is "nine hundred nine million, six hundred forty thousand, one hundred thirty-eight".