400220642 has 8 divisors (see below), whose sum is σ = 606520236. Its totient is φ = 198047232.

The previous prime is 400220603. The next prime is 400220657. The reversal of 400220642 is 246022004.

It can be written as a sum of positive squares in 2 ways, for example, as 383728921 + 16491721 = 19589^2 + 4061^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1031303 + ... + 1031690.

Almost surely, 2^400220642 is an apocalyptic number.

400220642 is a deficient number, since it is larger than the sum of its proper divisors (206299594).

400220642 is a wasteful number, since it uses less digits than its factorization.

400220642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2063092.

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 400220642 is about 20005.5152895395. The cubic root of 400220642 is about 736.9417501724.

Adding to 400220642 its reverse (246022004), we get a palindrome (646242646).

The spelling of 400220642 in words is "four hundred million, two hundred twenty thousand, six hundred forty-two".