400220664 has 64 divisors (see below), whose sum is σ = 1093616640. Its totient is φ = 121505280.

The previous prime is 400220663. The next prime is 400220671. The reversal of 400220664 is 466022004.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400220663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3174 + ... + 28469.

It is an arithmetic number, because the mean of its divisors is an integer number (17087760).

Almost surely, 2^400220664 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 400220664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (546808320).

400220664 is an abundant number, since it is smaller than the sum of its proper divisors (693395976).

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

400220664 is a wasteful number, since it uses less digits than its factorization.

400220664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31700 (or 31696 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

The square root of 400220664 is about 20005.5158393879. The cubic root of 400220664 is about 736.9417636756.

Adding to 400220664 its reverse (466022004), we get a palindrome (866242668).

The spelling of 400220664 in words is "four hundred million, two hundred twenty thousand, six hundred sixty-four".