728791668 has 60 divisors (see below), whose sum is σ = 2078416032. Its totient is φ = 220844880.

The previous prime is 728791667. The next prime is 728791697. The reversal of 728791668 is 866197827.

It is a super-2 number, since 2×728791668² = 1062274590692444448, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728791667) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 98680 + ... + 105807.

Almost surely, 2^728791668 is an apocalyptic number.

It is an amenable number.

728791668 is an abundant number, since it is smaller than the sum of its proper divisors (1349624364).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

728791668 is a wasteful number, since it uses less digits than its factorization.

728791668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204514 (or 204503 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 54.

The square root of 728791668 is about 26996.1417243279. The cubic root of 728791668 is about 899.9142584985.

Adding to 728791668 its product of digits (2032128), we get a triangular number (730823796 = T₃₈₂₃₁).

It can be divided in two parts, 72879 and 1668, that added together give a palindrome (74547).

The spelling of 728791668 in words is "seven hundred twenty-eight million, seven hundred ninety-one thousand, six hundred sixty-eight".