720765 has 32 divisors (see below), whose sum is σ = 1353600. Its totient is φ = 362880.

The previous prime is 720763. The next prime is 720767. The reversal of 720765 is 567027.

It is an interprime number because it is at equal distance from previous prime (720763) and next prime (720767).

It is not a de Polignac number, because 720765 - 2¹ = 720763 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720763) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2425 + ... + 2705.

It is an arithmetic number, because the mean of its divisors is an integer number (42300).

2⁷²⁰⁷⁶⁵ is an apocalyptic number.

It is an amenable number.

720765 is a deficient number, since it is larger than the sum of its proper divisors (632835).

720765 is a wasteful number, since it uses less digits than its factorization.

720765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314 (or 308 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 27.

The square root of 720765 is about 848.9787983218. The cubic root of 720765 is about 89.6598269790.

It can be divided in two parts, 720 and 765, that added together give a triangular number (1485 = T₅₄).

The spelling of 720765 in words is "seven hundred twenty thousand, seven hundred sixty-five".