1661297474843 has 2 divisors, whose sum is σ = 1661297474844. Its totient is φ = 1661297474842.

The previous prime is 1661297474831. The next prime is 1661297474849. The reversal of 1661297474843 is 3484747921661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1661297474843 - 2⁸ = 1661297474587 is a prime.

It is not a weakly prime, because it can be changed into another prime (1661297474849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830648737421 + 830648737422.

It is an arithmetic number, because the mean of its divisors is an integer number (830648737422).

Almost surely, 2^{1661297474843} is an apocalyptic number.

1661297474843 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661297474843 is an equidigital number, since it uses as much as digits as its factorization.

1661297474843 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48771072, while the sum is 62.

The spelling of 1661297474843 in words is "one trillion, six hundred sixty-one billion, two hundred ninety-seven million, four hundred seventy-four thousand, eight hundred forty-three".