400766688 has 144 divisors (see below), whose sum is σ = 1329400800. Its totient is φ = 114476544.

The previous prime is 400766683. The next prime is 400766699. The reversal of 400766688 is 886667004.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×400766688² = 321227876420978688, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400766683) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 96756 + ... + 100812.

It is an arithmetic number, because the mean of its divisors is an integer number (9231950).

Almost surely, 2^400766688 is an apocalyptic number.

400766688 is a gapful number since it is divisible by the number (48) 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 400766688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (664700400).

400766688 is an abundant number, since it is smaller than the sum of its proper divisors (928634112).

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

400766688 is a wasteful number, since it uses less digits than its factorization.

400766688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4094 (or 4069 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The square root of 400766688 is about 20019.1580242527. The cubic root of 400766688 is about 737.2767497393.

It can be divided in two parts, 40076 and 6688, that added together give a palindrome (46764).

The spelling of 400766688 in words is "four hundred million, seven hundred sixty-six thousand, six hundred eighty-eight".