40128842581 has 4 divisors (see below), whose sum is σ = 41213405932. Its totient is φ = 39044279232.

The previous prime is 40128842563. The next prime is 40128842623. The reversal of 40128842581 is 18524882104.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 26070946225 + 14057896356 = 161465^2 + 118566^2 .

It is a cyclic number.

It is not a de Polignac number, because 40128842581 - 2⁹ = 40128842069 is a prime.

It is a super-2 number, since 2×40128842581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40128842081) 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, 542281620 + ... + 542281693.

It is an arithmetic number, because the mean of its divisors is an integer number (10303351483).

Almost surely, 2^40128842581 is an apocalyptic number.

It is an amenable number.

40128842581 is a deficient number, since it is larger than the sum of its proper divisors (1084563351).

40128842581 is a wasteful number, since it uses less digits than its factorization.

40128842581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1084563350.

The product of its (nonzero) digits is 163840, while the sum is 43.

The spelling of 40128842581 in words is "forty billion, one hundred twenty-eight million, eight hundred forty-two thousand, five hundred eighty-one".