720531998 has 16 divisors (see below), whose sum is σ = 1097214336. Its totient is φ = 354805080.

The previous prime is 720531997. The next prime is 720532019. The reversal of 720531998 is 899135027.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720531997) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162965 + ... + 167327.

It is an arithmetic number, because the mean of its divisors is an integer number (68575896).

Almost surely, 2^720531998 is an apocalyptic number.

720531998 is a deficient number, since it is larger than the sum of its proper divisors (376682338).

720531998 is a wasteful number, since it uses less digits than its factorization.

720531998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5599.

The product of its (nonzero) digits is 136080, while the sum is 44.

The square root of 720531998 is about 26842.7270969252. The cubic root of 720531998 is about 896.5016448124.

The spelling of 720531998 in words is "seven hundred twenty million, five hundred thirty-one thousand, nine hundred ninety-eight".