725598778 has 4 divisors (see below), whose sum is σ = 1088398170. Its totient is φ = 362799388.

The previous prime is 725598767. The next prime is 725598829. The reversal of 725598778 is 877895527.

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., 544615569 + 180983209 = 23337^2 + 13453^2 .

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 181399693 + ... + 181399696.

Almost surely, 2^725598778 is an apocalyptic number.

725598778 is a deficient number, since it is larger than the sum of its proper divisors (362799392).

725598778 is a wasteful number, since it uses less digits than its factorization.

725598778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362799391.

The product of its digits is 9878400, while the sum is 58.

The square root of 725598778 is about 26936.9407691371. The cubic root of 725598778 is about 898.5981377230.

The spelling of 725598778 in words is "seven hundred twenty-five million, five hundred ninety-eight thousand, seven hundred seventy-eight".