40278393 has 18 divisors (see below), whose sum is σ = 60130122. Its totient is φ = 25980480.

The previous prime is 40278367. The next prime is 40278409. The reversal of 40278393 is 39387204.

It can be written as a sum of positive squares in only one way, i.e., 27123264 + 13155129 = 5208^2 + 3627^2 .

It is not a de Polignac number, because 40278393 - 2¹⁶ = 40212857 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (40278353) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 6321 + ... + 10977.

Almost surely, 2^40278393 is an apocalyptic number.

It is an amenable number.

40278393 is a deficient number, since it is larger than the sum of its proper divisors (19851729).

40278393 is a wasteful number, since it uses less digits than its factorization.

40278393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4725 (or 4691 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 40278393 is about 6346.5260576161. The cubic root of 40278393 is about 342.7867646467.

The spelling of 40278393 in words is "forty million, two hundred seventy-eight thousand, three hundred ninety-three".