1665430351997 has 2 divisors, whose sum is σ = 1665430351998. Its totient is φ = 1665430351996.

The previous prime is 1665430351993. The next prime is 1665430352023. The reversal of 1665430351997 is 7991530345661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1153967944441 + 511462407556 = 1074229^2 + 715166^2 .

It is a cyclic number.

It is not a de Polignac number, because 1665430351997 - 2² = 1665430351993 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1665430351993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832715175998 + 832715175999.

It is an arithmetic number, because the mean of its divisors is an integer number (832715175999).

Almost surely, 2^{1665430351997} is an apocalyptic number.

It is an amenable number.

1665430351997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665430351997 is an equidigital number, since it uses as much as digits as its factorization.

1665430351997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18370800, while the sum is 59.

The spelling of 1665430351997 in words is "one trillion, six hundred sixty-five billion, four hundred thirty million, three hundred fifty-one thousand, nine hundred ninety-seven".