661083318846719 has 16 divisors (see below), whose sum is σ = 719147570803488. Its totient is φ = 605161955515392.

The previous prime is 661083318846703. The next prime is 661083318846737. The reversal of 661083318846719 is 917648813380166.

It is a cyclic number.

It is not a de Polignac number, because 661083318846719 - 2⁴ = 661083318846703 is a prime.

It is a super-2 number, since 2×661083318846719² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661083318846779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 187487489 + ... + 190980954.

It is an arithmetic number, because the mean of its divisors is an integer number (44946723175218).

Almost surely, 2^{661083318846719} is an apocalyptic number.

661083318846719 is a deficient number, since it is larger than the sum of its proper divisors (58064251956769).

661083318846719 is a wasteful number, since it uses less digits than its factorization.

661083318846719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378471274.

The product of its (nonzero) digits is 250822656, while the sum is 71.

The spelling of 661083318846719 in words is "six hundred sixty-one trillion, eighty-three billion, three hundred eighteen million, eight hundred forty-six thousand, seven hundred nineteen".