491185561394 has 16 divisors (see below), whose sum is σ = 815754584736. Its totient is φ = 219933832800.

The previous prime is 491185561393. The next prime is 491185561409. The reversal of 491185561394 is 493165581194.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (491185561393) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 166615067 + ... + 166618014.

It is an arithmetic number, because the mean of its divisors is an integer number (50984661546).

Almost surely, 2^491185561394 is an apocalyptic number.

491185561394 is a deficient number, since it is larger than the sum of its proper divisors (324569023342).

491185561394 is a wasteful number, since it uses less digits than its factorization.

491185561394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333233161.

The product of its digits is 4665600, while the sum is 56.

The spelling of 491185561394 in words is "four hundred ninety-one billion, one hundred eighty-five million, five hundred sixty-one thousand, three hundred ninety-four".