40408993 has 2 divisors, whose sum is σ = 40408994. Its totient is φ = 40408992.

The previous prime is 40408981. The next prime is 40408997. The reversal of 40408993 is 39980404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31270464 + 9138529 = 5592^2 + 3023^2 .

It is a cyclic number.

It is not a de Polignac number, because 40408993 - 2⁵ = 40408961 is a prime.

It is not a weakly prime, because it can be changed into another prime (40408997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20204496 + 20204497.

It is an arithmetic number, because the mean of its divisors is an integer number (20204497).

Almost surely, 2^40408993 is an apocalyptic number.

It is an amenable number.

40408993 is a deficient number, since it is larger than the sum of its proper divisors (1).

40408993 is an equidigital number, since it uses as much as digits as its factorization.

40408993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 40408993 is about 6356.8068241846. The cubic root of 40408993 is about 343.1568526716.

The spelling of 40408993 in words is "forty million, four hundred eight thousand, nine hundred ninety-three".