1665977849 has 8 divisors (see below), whose sum is σ = 1774801440. Its totient is φ = 1558357056.

The previous prime is 1665977843. The next prime is 1665977857. The reversal of 1665977849 is 9487795661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1665977849 - 2¹² = 1665973753 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1665977791 and 1665977800.

It is not an unprimeable number, because it can be changed into a prime (1665977843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 297839 + ... + 303380.

It is an arithmetic number, because the mean of its divisors is an integer number (221850180).

Almost surely, 2^1665977849 is an apocalyptic number.

It is an amenable number.

1665977849 is a deficient number, since it is larger than the sum of its proper divisors (108823591).

1665977849 is a wasteful number, since it uses less digits than its factorization.

1665977849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 601399.

The product of its digits is 22861440, while the sum is 62.

The square root of 1665977849 is about 40816.3919155038. The cubic root of 1665977849 is about 1185.4677422599.

The spelling of 1665977849 in words is "one billion, six hundred sixty-five million, nine hundred seventy-seven thousand, eight hundred forty-nine".