40013720 has 32 divisors (see below), whose sum is σ = 90882000. Its totient is φ = 15854208.

The previous prime is 40013713. The next prime is 40013723. The reversal of 40013720 is 2731004.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40013723) 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, 395 + ... + 8954.

Almost surely, 2^40013720 is an apocalyptic number.

40013720 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

40013720 is an abundant number, since it is smaller than the sum of its proper divisors (50868280).

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

40013720 is a wasteful number, since it uses less digits than its factorization.

40013720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9467 (or 9463 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 17.

The square root of 40013720 is about 6325.6398885804. The cubic root of 40013720 is about 342.0342863156.

Adding to 40013720 its reverse (2731004), we get a palindrome (42744724).

The spelling of 40013720 in words is "forty million, thirteen thousand, seven hundred twenty".