401568678557 has 4 divisors (see below), whose sum is σ = 403234938876. Its totient is φ = 399902418240.

The previous prime is 401568678527. The next prime is 401568678559. The reversal of 401568678557 is 755876865104.

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

It can be written as a sum of positive squares in 2 ways, for example, as 371424426916 + 30144251641 = 609446^2 + 173621^2 .

It is a cyclic number.

It is not a de Polignac number, because 401568678557 - 2⁶ = 401568678493 is a prime.

It is a super-3 number, since 3×401568678557³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 401568678557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401568678559) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 833129798 + ... + 833130279.

It is an arithmetic number, because the mean of its divisors is an integer number (100808734719).

Almost surely, 2^401568678557 is an apocalyptic number.

It is an amenable number.

401568678557 is a deficient number, since it is larger than the sum of its proper divisors (1666260319).

401568678557 is a wasteful number, since it uses less digits than its factorization.

401568678557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1666260318.

The product of its (nonzero) digits is 56448000, while the sum is 62.

The spelling of 401568678557 in words is "four hundred one billion, five hundred sixty-eight million, six hundred seventy-eight thousand, five hundred fifty-seven".