40278381 has 16 divisors (see below), whose sum is σ = 63094080. Its totient is φ = 22533120.

The previous prime is 40278367. The next prime is 40278409. The reversal of 40278381 is 18387204.

It is not a de Polignac number, because 40278381 - 2⁵ = 40278349 is a prime.

It is a super-2 number, since 2×40278381² = 3244695951962322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40278181) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46516 + ... + 47373.

It is an arithmetic number, because the mean of its divisors is an integer number (3943380).

Almost surely, 2^40278381 is an apocalyptic number.

It is an amenable number.

40278381 is a deficient number, since it is larger than the sum of its proper divisors (22815699).

40278381 is a wasteful number, since it uses less digits than its factorization.

40278381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93916.

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 40278381 is about 6346.5251122169. The cubic root of 40278381 is about 342.7867306050.

The spelling of 40278381 in words is "forty million, two hundred seventy-eight thousand, three hundred eighty-one".