40138440 has 32 divisors (see below), whose sum is σ = 120415680. Its totient is φ = 10703552.

The previous prime is 40138429. The next prime is 40138447. The reversal of 40138440 is 4483104.

It is a super-2 number, since 2×40138440² = 3222188731267200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 40138440.

It is not an unprimeable number, because it can be changed into a prime (40138447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 167124 + ... + 167363.

It is an arithmetic number, because the mean of its divisors is an integer number (3762990).

Almost surely, 2^40138440 is an apocalyptic number.

40138440 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

40138440 is an abundant number, since it is smaller than the sum of its proper divisors (80277240).

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

40138440 is a wasteful number, since it uses less digits than its factorization.

40138440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334501 (or 334497 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 40138440 is about 6335.4905098185. The cubic root of 40138440 is about 342.3892834812.

The spelling of 40138440 in words is "forty million, one hundred thirty-eight thousand, four hundred forty".