766728989 has 16 divisors (see below), whose sum is σ = 863796864. Its totient is φ = 675259200.

The previous prime is 766728979. The next prime is 766728997. The reversal of 766728989 is 989827667.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 766728989 - 2⁴ = 766728973 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (766728979) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122834 + ... + 128924.

It is an arithmetic number, because the mean of its divisors is an integer number (53987304).

Almost surely, 2^766728989 is an apocalyptic number.

It is an amenable number.

766728989 is a deficient number, since it is larger than the sum of its proper divisors (97067875).

766728989 is a wasteful number, since it uses less digits than its factorization.

766728989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6548.

The product of its digits is 18289152, while the sum is 62.

The square root of 766728989 is about 27689.8715959464. The cubic root of 766728989 is about 915.2659260708.

The spelling of 766728989 in words is "seven hundred sixty-six million, seven hundred twenty-eight thousand, nine hundred eighty-nine".