40812138 has 48 divisors (see below), whose sum is σ = 95940936. Its totient is φ = 12487680.

The previous prime is 40812137. The next prime is 40812139. The reversal of 40812138 is 83121804.

It is an interprime number because it is at equal distance from previous prime (40812137) and next prime (40812139).

It can be written as a sum of positive squares in 4 ways, for example, as 39652209 + 1159929 = 6297^2 + 1077^2 .

It is not an unprimeable number, because it can be changed into a prime (40812131) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10920 + ... + 14172.

Almost surely, 2^40812138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40812138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47970468).

40812138 is an abundant number, since it is smaller than the sum of its proper divisors (55128798).

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

40812138 is a wasteful number, since it uses less digits than its factorization.

40812138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3319 (or 3316 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 40812138 is about 6388.4378372181. The cubic root of 40812138 is about 344.2942598893.

The spelling of 40812138 in words is "forty million, eight hundred twelve thousand, one hundred thirty-eight".