45138240 has 168 divisors, whose sum is σ = 177515520. Its totient is φ = 10312704.

The previous prime is 45138227. The next prime is 45138241. The reversal of 45138240 is 4283154.

It is a tau number, because it is divible by the number of its divisors (168).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (45138241) 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, 19041 + ... + 21279.

It is an arithmetic number, because the mean of its divisors is an integer number (1056640).

Almost surely, 2^45138240 is an apocalyptic number.

45138240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 45138240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88757760).

45138240 is an abundant number, since it is smaller than the sum of its proper divisors (132377280).

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

45138240 is a wasteful number, since it uses less digits than its factorization.

45138240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2269 (or 2256 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 45138240 is about 6718.4998325519. The cubic root of 45138240 is about 356.0531839913.

The spelling of 45138240 in words is "forty-five million, one hundred thirty-eight thousand, two hundred forty".