400399994 has 4 divisors (see below), whose sum is σ = 600599994. Its totient is φ = 200199996.

The previous prime is 400399949. The next prime is 400400041. The reversal of 400399994 is 499993004.

It is a happy number.

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., 381694369 + 18705625 = 19537^2 + 4325^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100099997 + ... + 100100000.

Almost surely, 2^400399994 is an apocalyptic number.

400399994 is a deficient number, since it is larger than the sum of its proper divisors (200200000).

400399994 is a wasteful number, since it uses less digits than its factorization.

400399994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200199999.

The product of its (nonzero) digits is 314928, while the sum is 47.

The square root of 400399994 is about 20009.9973513242. The cubic root of 400399994 is about 737.0518163245.

The spelling of 400399994 in words is "four hundred million, three hundred ninety-nine thousand, nine hundred ninety-four".