40331781 has 48 divisors (see below), whose sum is σ = 69548544. Its totient is φ = 22044672.

The previous prime is 40331777. The next prime is 40331827. The reversal of 40331781 is 18713304.

40331781 = 173² + 174² + ... + 501².

It is not a de Polignac number, because 40331781 - 2² = 40331777 is a prime.

It is a super-2 number, since 2×40331781² = 3253305117263922, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40331761) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 156805 + ... + 157061.

It is an arithmetic number, because the mean of its divisors is an integer number (1448928).

Almost surely, 2^40331781 is an apocalyptic number.

It is an amenable number.

40331781 is a deficient number, since it is larger than the sum of its proper divisors (29216763).

40331781 is a wasteful number, since it uses less digits than its factorization.

40331781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 370 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 40331781 is about 6350.7307453552. The cubic root of 40331781 is about 342.9381495347.

The spelling of 40331781 in words is "forty million, three hundred thirty-one thousand, seven hundred eighty-one".