40008643 has 2 divisors, whose sum is σ = 40008644. Its totient is φ = 40008642.

The previous prime is 40008637. The next prime is 40008649. The reversal of 40008643 is 34680004.

It is a balanced prime because it is at equal distance from previous prime (40008637) and next prime (40008649).

It is a cyclic number.

It is not a de Polignac number, because 40008643 - 2¹³ = 40000451 is a prime.

It is not a weakly prime, because it can be changed into another prime (40008649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20004321 + 20004322.

It is an arithmetic number, because the mean of its divisors is an integer number (20004322).

Almost surely, 2^40008643 is an apocalyptic number.

40008643 is a deficient number, since it is larger than the sum of its proper divisors (1).

40008643 is an equidigital number, since it uses as much as digits as its factorization.

40008643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 40008643 is about 6325.2385725757. The cubic root of 40008643 is about 342.0198197649.

Adding to 40008643 its reverse (34680004), we get a palindrome (74688647).

The spelling of 40008643 in words is "forty million, eight thousand, six hundred forty-three".