1719661361 has 4 divisors (see below), whose sum is σ = 1875994224. Its totient is φ = 1563328500.

The previous prime is 1719661351. The next prime is 1719661369. The reversal of 1719661361 is 1631669171.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1631669171 = 11 ⋅148333561.

It is a cyclic number.

It is not a de Polignac number, because 1719661361 - 2¹⁰ = 1719660337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1719661369) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 78166415 + ... + 78166436.

It is an arithmetic number, because the mean of its divisors is an integer number (468998556).

Almost surely, 2^1719661361 is an apocalyptic number.

1719661361 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1719661361 is a deficient number, since it is larger than the sum of its proper divisors (156332863).

1719661361 is a wasteful number, since it uses less digits than its factorization.

1719661361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156332862.

The product of its digits is 40824, while the sum is 41.

The square root of 1719661361 is about 41468.7998500077. The cubic root of 1719661361 is about 1198.0666462831.

The spelling of 1719661361 in words is "one billion, seven hundred nineteen million, six hundred sixty-one thousand, three hundred sixty-one".