400641012 has 96 divisors (see below), whose sum is σ = 1072229760. Its totient is φ = 129288960.

The previous prime is 400640959. The next prime is 400641013. The reversal of 400641012 is 210146004.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400641013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 765783 + ... + 766305.

It is an arithmetic number, because the mean of its divisors is an integer number (11169060).

Almost surely, 2^400641012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400641012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (536114880).

400641012 is an abundant number, since it is smaller than the sum of its proper divisors (671588748).

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

400641012 is a wasteful number, since it uses less digits than its factorization.

400641012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750 (or 742 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 400641012 is about 20016.0188848832. The cubic root of 400641012 is about 737.1996744044.

Adding to 400641012 its reverse (210146004), we get a palindrome (610787016).

The spelling of 400641012 in words is "four hundred million, six hundred forty-one thousand, twelve".