40405215400 has 72 divisors (see below), whose sum is σ = 103258762110. Its totient is φ = 14692796800.

The previous prime is 40405215397. The next prime is 40405215401. The reversal of 40405215400 is 451250404.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 16546705956 + 23858509444 = 128634^2 + 154462^2 .

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (40405215401) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 810619 + ... + 859018.

Almost surely, 2^40405215400 is an apocalyptic number.

40405215400 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

40405215400 is an abundant number, since it is smaller than the sum of its proper divisors (62853546710).

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

40405215400 is a wasteful number, since it uses less digits than its factorization.

40405215400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1669675 (or 1669655 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 25.

Adding to 40405215400 its reverse (451250404), we get a palindrome (40856465804).

The spelling of 40405215400 in words is "forty billion, four hundred five million, two hundred fifteen thousand, four hundred".