40787729 has 2 divisors, whose sum is σ = 40787730. Its totient is φ = 40787728.

The previous prime is 40787683. The next prime is 40787731. The reversal of 40787729 is 92778704.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30547729 + 10240000 = 5527^2 + 3200^2 .

It is a cyclic number.

It is not a de Polignac number, because 40787729 - 2¹⁶ = 40722193 is a prime.

Together with 40787731, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 40787729.

It is not a weakly prime, because it can be changed into another prime (40787749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20393864 + 20393865.

It is an arithmetic number, because the mean of its divisors is an integer number (20393865).

Almost surely, 2^40787729 is an apocalyptic number.

It is an amenable number.

40787729 is a deficient number, since it is larger than the sum of its proper divisors (1).

40787729 is an equidigital number, since it uses as much as digits as its factorization.

40787729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 197568, while the sum is 44.

The square root of 40787729 is about 6386.5271470495. The cubic root of 40787729 is about 344.2256074821.

The spelling of 40787729 in words is "forty million, seven hundred eighty-seven thousand, seven hundred twenty-nine".