6401197555 has 4 divisors (see below), whose sum is σ = 7681437072. Its totient is φ = 5120958040.

The previous prime is 6401197553. The next prime is 6401197573. The reversal of 6401197555 is 5557911046.

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

It is not a de Polignac number, because 6401197555 - 2¹ = 6401197553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6401197553) 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, 640119751 + ... + 640119760.

It is an arithmetic number, because the mean of its divisors is an integer number (1920359268).

Almost surely, 2^6401197555 is an apocalyptic number.

6401197555 is a deficient number, since it is larger than the sum of its proper divisors (1280239517).

6401197555 is a wasteful number, since it uses less digits than its factorization.

6401197555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1280239516.

The product of its (nonzero) digits is 189000, while the sum is 43.

The square root of 6401197555 is about 80007.4843686514. The cubic root of 6401197555 is about 1856.7513295128.

The spelling of 6401197555 in words is "six billion, four hundred one million, one hundred ninety-seven thousand, five hundred fifty-five".