40438581 has 4 divisors (see below), whose sum is σ = 53918112. Its totient is φ = 26959052.

The previous prime is 40438571. The next prime is 40438583. The reversal of 40438581 is 18583404.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40438581 - 2²³ = 32049973 is a prime.

It is a super-2 number, since 2×40438581² = 3270557666587122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40438583) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6739761 + ... + 6739766.

It is an arithmetic number, because the mean of its divisors is an integer number (13479528).

Almost surely, 2^40438581 is an apocalyptic number.

It is an amenable number.

40438581 is a deficient number, since it is larger than the sum of its proper divisors (13479531).

40438581 is a wasteful number, since it uses less digits than its factorization.

40438581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13479530.

The product of its (nonzero) digits is 15360, while the sum is 33.

The square root of 40438581 is about 6359.1336674110. The cubic root of 40438581 is about 343.2405869024.

The spelling of 40438581 in words is "forty million, four hundred thirty-eight thousand, five hundred eighty-one".