40001000 has 128 divisors (see below), whose sum is σ = 107321760. Its totient is φ = 13824000.

The previous prime is 40000993. The next prime is 40001021. The reversal of 40001000 is 10004.

40001000 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 16 ways, for example, as 12773476 + 27227524 = 3574^2 + 5218^2 .

It is a Harshad number since it is a multiple of its sum of digits (5).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 220910 + ... + 221090.

Almost surely, 2^40001000 is an apocalyptic number.

40001000 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 40001000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53660880).

40001000 is an abundant number, since it is smaller than the sum of its proper divisors (67320760).

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

40001000 is a wasteful number, since it uses less digits than its factorization.

40001000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232 (or 218 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 5.

The square root of 40001000 is about 6324.6343767842. The cubic root of 40001000 is about 341.9980392715.

Adding to 40001000 its reverse (10004), we get a palindrome (40011004).

The spelling of 40001000 in words is "forty million, one thousand".