400412640 has 96 divisors (see below), whose sum is σ = 1270715040. Its totient is φ = 105979904.

The previous prime is 400412629. The next prime is 400412653. The reversal of 400412640 is 46214004.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62716 + ... + 68804.

It is an arithmetic number, because the mean of its divisors is an integer number (13236615).

Almost surely, 2^400412640 is an apocalyptic number.

400412640 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 400412640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (635357520).

400412640 is an abundant number, since it is smaller than the sum of its proper divisors (870302400).

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

400412640 is a wasteful number, since it uses less digits than its factorization.

400412640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6244 (or 6236 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 400412640 is about 20010.3133408750. The cubic root of 400412640 is about 737.0595757811.

Adding to 400412640 its reverse (46214004), we get a palindrome (446626644).

The spelling of 400412640 in words is "four hundred million, four hundred twelve thousand, six hundred forty".