689731379728 has 10 divisors (see below), whose sum is σ = 1336354548254. Its totient is φ = 344865689856.

The previous prime is 689731379719. The next prime is 689731379747. The reversal of 689731379728 is 827973137986.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 529244610064 + 160486769664 = 727492^2 + 400608^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21554105601 + ... + 21554105632.

Almost surely, 2^689731379728 is an apocalyptic number.

It is an amenable number.

689731379728 is a deficient number, since it is larger than the sum of its proper divisors (646623168526).

689731379728 is a wasteful number, since it uses less digits than its factorization.

689731379728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43108211241 (or 43108211235 counting only the distinct ones).

The product of its digits is 192036096, while the sum is 70.

The spelling of 689731379728 in words is "six hundred eighty-nine billion, seven hundred thirty-one million, three hundred seventy-nine thousand, seven hundred twenty-eight".