400344780 has 96 divisors (see below), whose sum is σ = 1234517760. Its totient is φ = 96129280.

The previous prime is 400344761. The next prime is 400344793. The reversal of 400344780 is 87443004.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

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, 67786 + ... + 73454.

It is an arithmetic number, because the mean of its divisors is an integer number (12859560).

Almost surely, 2^400344780 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 400344780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (617258880).

400344780 is an abundant number, since it is smaller than the sum of its proper divisors (834172980).

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

400344780 is a wasteful number, since it uses less digits than its factorization.

400344780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5799 (or 5797 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 30.

The square root of 400344780 is about 20008.6176434056. The cubic root of 400344780 is about 737.0179356632.

Adding to 400344780 its reverse (87443004), we get a palindrome (487787784).

The spelling of 400344780 in words is "four hundred million, three hundred forty-four thousand, seven hundred eighty".