720551 has 8 divisors (see below), whose sum is σ = 794640. Its totient is φ = 649152.

The previous prime is 720547. The next prime is 720569. The reversal of 720551 is 155027.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 720551 - 2² = 720547 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 720551.

It is not an unprimeable number, because it can be changed into a prime (720571) 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, 86 + ... + 1203.

It is an arithmetic number, because the mean of its divisors is an integer number (99330).

2⁷²⁰⁵⁵¹ is an apocalyptic number.

720551 is a deficient number, since it is larger than the sum of its proper divisors (74089).

720551 is a wasteful number, since it uses less digits than its factorization.

720551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1345.

The product of its (nonzero) digits is 350, while the sum is 20.

The square root of 720551 is about 848.8527551937. The cubic root of 720551 is about 89.6509525644.

Adding to 720551 its reverse (155027), we get a palindrome (875578).

The spelling of 720551 in words is "seven hundred twenty thousand, five hundred fifty-one".