40409928 has 168 divisors, whose sum is σ = 126011970. Its totient is φ = 12130560.

The previous prime is 40409921. The next prime is 40409959. The reversal of 40409928 is 82990404.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 9474084 + 30935844 = 3078^2 + 5562^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 40409892 and 40409901.

It is not an unprimeable number, because it can be changed into a prime (40409921) 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 41 ways as a sum of consecutive naturals, for example, 985588 + ... + 985628.

Almost surely, 2^40409928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40409928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63005985).

40409928 is an abundant number, since it is smaller than the sum of its proper divisors (85602042).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

40409928 is a wasteful number, since it uses less digits than its factorization.

40409928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 40409928 is about 6356.8803669725. The cubic root of 40409928 is about 343.1594993530.

The spelling of 40409928 in words is "forty million, four hundred nine thousand, nine hundred twenty-eight".