40012581 has 8 divisors (see below), whose sum is σ = 60971584. Its totient is φ = 22864320.

The previous prime is 40012573. The next prime is 40012589. The reversal of 40012581 is 18521004.

It is an interprime number because it is at equal distance from previous prime (40012573) and next prime (40012589).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 40012581 - 2³ = 40012573 is a prime.

It is a super-2 number, since 2×40012581² = 3202013276563122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 1905361 = 40012581 / (4 + 0 + 0 + 1 + 2 + 5 + 8 + 1).

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40012589) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 952660 + ... + 952701.

It is an arithmetic number, because the mean of its divisors is an integer number (7621448).

Almost surely, 2^40012581 is an apocalyptic number.

It is an amenable number.

40012581 is a deficient number, since it is larger than the sum of its proper divisors (20959003).

40012581 is a wasteful number, since it uses less digits than its factorization.

40012581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1905371.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 40012581 is about 6325.5498575223. The cubic root of 40012581 is about 342.0310409225.

Adding to 40012581 its reverse (18521004), we get a palindrome (58533585).

The spelling of 40012581 in words is "forty million, twelve thousand, five hundred eighty-one".