1649940866 has 8 divisors (see below), whose sum is σ = 2828470080. Its totient is φ = 707117508.

The previous prime is 1649940823. The next prime is 1649940881. The reversal of 1649940866 is 6680499461.

It is a happy number.

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

It is a super-2 number, since 2×1649940866² = 5444609722593659912, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58926446 + ... + 58926473.

It is an arithmetic number, because the mean of its divisors is an integer number (353558760).

Almost surely, 2^1649940866 is an apocalyptic number.

1649940866 is a deficient number, since it is larger than the sum of its proper divisors (1178529214).

1649940866 is a wasteful number, since it uses less digits than its factorization.

1649940866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117852928.

The product of its (nonzero) digits is 2239488, while the sum is 53.

The square root of 1649940866 is about 40619.4641274353. The cubic root of 1649940866 is about 1181.6516338095.

The spelling of 1649940866 in words is "one billion, six hundred forty-nine million, nine hundred forty thousand, eight hundred sixty-six".