725661999 has 12 divisors (see below), whose sum is σ = 1070480736. Its totient is φ = 473481312.

The previous prime is 725661997. The next prime is 725662001. The reversal of 725661999 is 999166527.

725661999 is a `hidden beast` number, since 72 + 566 + 1 + 9 + 9 + 9 = 666.

725661999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (725661997) and next prime (725662001).

It is not a de Polignac number, because 725661999 - 2¹ = 725661997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (725661997) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 857334 + ... + 858179.

It is an arithmetic number, because the mean of its divisors is an integer number (89206728).

Almost surely, 2^725661999 is an apocalyptic number.

725661999 is a deficient number, since it is larger than the sum of its proper divisors (344818737).

725661999 is a wasteful number, since it uses less digits than its factorization.

725661999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1715566 (or 1715563 counting only the distinct ones).

The product of its digits is 1837080, while the sum is 54.

The square root of 725661999 is about 26938.1142435769. The cubic root of 725661999 is about 898.6242350763.

The spelling of 725661999 in words is "seven hundred twenty-five million, six hundred sixty-one thousand, nine hundred ninety-nine".