6401956394 has 4 divisors (see below), whose sum is σ = 9602934594. Its totient is φ = 3200978196.

The previous prime is 6401956381. The next prime is 6401956399. The reversal of 6401956394 is 4936591046.

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., 6191329225 + 210627169 = 78685^2 + 14513^2 .

It is not an unprimeable number, because it can be changed into a prime (6401956399) by changing a digit.

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 as a sum of consecutive naturals, namely, 1600489097 + ... + 1600489100.

Almost surely, 2^6401956394 is an apocalyptic number.

6401956394 is a deficient number, since it is larger than the sum of its proper divisors (3200978200).

6401956394 is a wasteful number, since it uses less digits than its factorization.

6401956394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3200978199.

The product of its (nonzero) digits is 699840, while the sum is 47.

The square root of 6401956394 is about 80012.2265282001. The cubic root of 6401956394 is about 1856.8246970162.

The spelling of 6401956394 in words is "six billion, four hundred one million, nine hundred fifty-six thousand, three hundred ninety-four".