400423978 has 8 divisors (see below), whose sum is σ = 600808068. Its totient is φ = 200154624.

The previous prime is 400423963. The next prime is 400423979. The reversal of 400423978 is 879324004.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 389154529 + 11269449 = 19727^2 + 3357^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (400423979) 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 3 ways as a sum of consecutive naturals, for example, 19351 + ... + 34282.

Almost surely, 2^400423978 is an apocalyptic number.

400423978 is a deficient number, since it is larger than the sum of its proper divisors (200384090).

400423978 is a wasteful number, since it uses less digits than its factorization.

400423978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57368.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 400423978 is about 20010.5966427790. The cubic root of 400423978 is about 737.0665325234.

The spelling of 400423978 in words is "four hundred million, four hundred twenty-three thousand, nine hundred seventy-eight".