400866778 has 32 divisors (see below), whose sum is σ = 657456912. Its totient is φ = 182208000.

The previous prime is 400866761. The next prime is 400866779. The reversal of 400866778 is 877668004.

It can be written as a sum of positive squares in 8 ways, for example, as 301126609 + 99740169 = 17353^2 + 9987^2 .

It is not an unprimeable number, because it can be changed into a prime (400866779) by changing a digit.

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, 769158 + ... + 769678.

Almost surely, 2^400866778 is an apocalyptic number.

400866778 is a deficient number, since it is larger than the sum of its proper divisors (256590134).

400866778 is a wasteful number, since it uses less digits than its factorization.

400866778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 930.

The product of its (nonzero) digits is 451584, while the sum is 46.

The square root of 400866778 is about 20021.6577235752. The cubic root of 400866778 is about 737.3381220120.

It can be divided in two parts, 40086 and 6778, that added together give a palindrome (46864).

The spelling of 400866778 in words is "four hundred million, eight hundred sixty-six thousand, seven hundred seventy-eight".