40400000 has 96 divisors (see below), whose sum is σ = 101595060. Its totient is φ = 16000000.

The previous prime is 40399981. The next prime is 40400011. The reversal of 40400000 is 404.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 153664 + 40246336 = 392^2 + 6344^2 .

It is a Harshad number since it is a multiple of its sum of digits (8).

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 polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 399950 + ... + 400050.

Almost surely, 2^40400000 is an apocalyptic number.

40400000 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 40400000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50797530).

40400000 is an abundant number, since it is smaller than the sum of its proper divisors (61195060).

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

40400000 is an frugal number, since it uses more digits than its factorization.

40400000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 108 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 8.

The square root of 40400000 is about 6356.0994328283. The cubic root of 40400000 is about 343.1313943243.

Adding to 40400000 its reverse (404), we get a palindrome (40400404).

40400000 divided by its reverse (404) gives a 5-th power (100000 = 10⁵).

It can be divided in two parts, 40 and 400000, that multiplied together give a square (16000000 = 4000²).

The spelling of 40400000 in words is "forty million, four hundred thousand".