720091 has 2 divisors, whose sum is σ = 720092. Its totient is φ = 720090.

The previous prime is 720089. The next prime is 720101. The reversal of 720091 is 190027.

It is a weak prime.

It is an emirp because it is prime and its reverse (190027) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 720091 - 2¹ = 720089 is a prime.

Together with 720089, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (720491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360045 + 360046.

It is an arithmetic number, because the mean of its divisors is an integer number (360046).

2⁷²⁰⁰⁹¹ is an apocalyptic number.

720091 is a deficient number, since it is larger than the sum of its proper divisors (1).

720091 is an equidigital number, since it uses as much as digits as its factorization.

720091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 126, while the sum is 19.

The square root of 720091 is about 848.5817579939. The cubic root of 720091 is about 89.6318707705.

It can be divided in two parts, 72009 and 1, that added together give a triangular number (72010 = T₃₇₉).

The spelling of 720091 in words is "seven hundred twenty thousand, ninety-one".