400627978 has 4 divisors (see below), whose sum is σ = 600941970. Its totient is φ = 200313988.

The previous prime is 400627963. The next prime is 400627979. The reversal of 400627978 is 879726004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 336098889 + 64529089 = 18333^2 + 8033^2 .

It is not an unprimeable number, because it can be changed into a prime (400627979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100156993 + ... + 100156996.

Almost surely, 2^400627978 is an apocalyptic number.

400627978 is a deficient number, since it is larger than the sum of its proper divisors (200313992).

400627978 is a wasteful number, since it uses less digits than its factorization.

400627978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200313991.

The product of its (nonzero) digits is 169344, while the sum is 43.

The square root of 400627978 is about 20015.6932930139. The cubic root of 400627978 is about 737.1916799119.

The spelling of 400627978 in words is "four hundred million, six hundred twenty-seven thousand, nine hundred seventy-eight".