1661902799 has 2 divisors, whose sum is σ = 1661902800. Its totient is φ = 1661902798.

The previous prime is 1661902793. The next prime is 1661902807. The reversal of 1661902799 is 9972091661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1661902799 - 2²⁸ = 1393467343 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661902793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830951399 + 830951400.

It is an arithmetic number, because the mean of its divisors is an integer number (830951400).

Almost surely, 2^1661902799 is an apocalyptic number.

1661902799 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661902799 is an equidigital number, since it uses as much as digits as its factorization.

1661902799 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 367416, while the sum is 50.

The square root of 1661902799 is about 40766.4420694276. The cubic root of 1661902799 is about 1184.5003855614.

The spelling of 1661902799 in words is "one billion, six hundred sixty-one million, nine hundred two thousand, seven hundred ninety-nine".