1749664661 has 2 divisors, whose sum is σ = 1749664662. Its totient is φ = 1749664660.

The previous prime is 1749664643. The next prime is 1749664663. The reversal of 1749664661 is 1664669471.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1042902436 + 706762225 = 32294^2 + 26585^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1749664661 is a prime.

It is a super-2 number, since 2×1749664661² = 6122652851904489842, which contains 22 as substring.

Together with 1749664663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1749664663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 874832330 + 874832331.

It is an arithmetic number, because the mean of its divisors is an integer number (874832331).

Almost surely, 2^1749664661 is an apocalyptic number.

It is an amenable number.

1749664661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1749664661 is an equidigital number, since it uses as much as digits as its factorization.

1749664661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1306368, while the sum is 50.

The square root of 1749664661 is about 41828.9930670104. The cubic root of 1749664661 is about 1204.9941543423.

The spelling of 1749664661 in words is "one billion, seven hundred forty-nine million, six hundred sixty-four thousand, six hundred sixty-one".