40128642 has 16 divisors (see below), whose sum is σ = 89174880. Its totient is φ = 13376196.

The previous prime is 40128631. The next prime is 40128643. The reversal of 40128642 is 24682104.

40128642 is a `hidden beast` number, since 4 + 0 + 12 + 8 + 642 = 666.

It is a super-2 number, since 2×40128642² = 3220615817528328, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (40128643) 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, 371508 + ... + 371615.

It is an arithmetic number, because the mean of its divisors is an integer number (5573430).

Almost surely, 2^40128642 is an apocalyptic number.

40128642 is an abundant number, since it is smaller than the sum of its proper divisors (49046238).

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

40128642 is a wasteful number, since it uses less digits than its factorization.

40128642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 743134 (or 743128 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 40128642 is about 6334.7171996862. The cubic root of 40128642 is about 342.3614215513.

The spelling of 40128642 in words is "forty million, one hundred twenty-eight thousand, six hundred forty-two".