728702978 has 4 divisors (see below), whose sum is σ = 1093054470. Its totient is φ = 364351488.

The previous prime is 728702971. The next prime is 728702999. The reversal of 728702978 is 879207827.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 685235329 + 43467649 = 26177^2 + 6593^2 .

It is not an unprimeable number, because it can be changed into a prime (728702971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 182175743 + ... + 182175746.

Almost surely, 2^728702978 is an apocalyptic number.

728702978 is a deficient number, since it is larger than the sum of its proper divisors (364351492).

728702978 is a wasteful number, since it uses less digits than its factorization.

728702978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364351491.

The product of its (nonzero) digits is 790272, while the sum is 50.

The square root of 728702978 is about 26994.4990322102. The cubic root of 728702978 is about 899.8777521200.

The spelling of 728702978 in words is "seven hundred twenty-eight million, seven hundred two thousand, nine hundred seventy-eight".