40379981 has 16 divisors (see below), whose sum is σ = 43856640. Its totient is φ = 37040640.

The previous prime is 40379971. The next prime is 40379993. The reversal of 40379981 is 18997304.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40379981 is a prime.

It is a super-2 number, since 2×40379981² = 3261085731120722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40379951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 143561 + ... + 143841.

It is an arithmetic number, because the mean of its divisors is an integer number (2741040).

Almost surely, 2^40379981 is an apocalyptic number.

It is an amenable number.

40379981 is a deficient number, since it is larger than the sum of its proper divisors (3476659).

40379981 is a wasteful number, since it uses less digits than its factorization.

40379981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 40379981 is about 6354.5244511293. The cubic root of 40379981 is about 343.0747088269.

The spelling of 40379981 in words is "forty million, three hundred seventy-nine thousand, nine hundred eighty-one".