145694440039661 has 2 divisors, whose sum is σ = 145694440039662. Its totient is φ = 145694440039660.

The previous prime is 145694440039639. The next prime is 145694440039691. The reversal of 145694440039661 is 166930044496541.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 83776127584900 + 61918312454761 = 9152930^2 + 7868819^2 .

It is an emirp because it is prime and its reverse (166930044496541) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-145694440039661 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 145694440039594 and 145694440039603.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145694440039691) 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, 72847220019830 + 72847220019831.

It is an arithmetic number, because the mean of its divisors is an integer number (72847220019831).

Almost surely, 2^{145694440039661} is an apocalyptic number.

It is an amenable number.

145694440039661 is a deficient number, since it is larger than the sum of its proper divisors (1).

145694440039661 is an equidigital number, since it uses as much as digits as its factorization.

145694440039661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 67184640, while the sum is 62.

The spelling of 145694440039661 in words is "one hundred forty-five trillion, six hundred ninety-four billion, four hundred forty million, thirty-nine thousand, six hundred sixty-one".