40390065 has 12 divisors (see below), whose sum is σ = 70009524. Its totient is φ = 21541344.

The previous prime is 40390037. The next prime is 40390073. The reversal of 40390065 is 56009304.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 6796449 + 33593616 = 2607^2 + 5796^2 .

It is not a de Polignac number, because 40390065 - 2⁵ = 40390033 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 448734 + ... + 448823.

It is an arithmetic number, because the mean of its divisors is an integer number (5834127).

Almost surely, 2^40390065 is an apocalyptic number.

40390065 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

40390065 is a deficient number, since it is larger than the sum of its proper divisors (29619459).

40390065 is a wasteful number, since it uses less digits than its factorization.

40390065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 897568 (or 897565 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 40390065 is about 6355.3178520039. The cubic root of 40390065 is about 343.1032648699.

Adding to 40390065 its reverse (56009304), we get a palindrome (96399369).

The spelling of 40390065 in words is "forty million, three hundred ninety thousand, sixty-five".