720145523 has 4 divisors (see below), whose sum is σ = 721906680. Its totient is φ = 718384368.

The previous prime is 720145507. The next prime is 720145529. The reversal of 720145523 is 325541027.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 325541027 = 7 ⋅46505861.

It is a cyclic number.

It is not a de Polignac number, because 720145523 - 2⁴ = 720145507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (720145529) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 879965 + ... + 880782.

It is an arithmetic number, because the mean of its divisors is an integer number (180476670).

Almost surely, 2^720145523 is an apocalyptic number.

720145523 is a deficient number, since it is larger than the sum of its proper divisors (1761157).

720145523 is a wasteful number, since it uses less digits than its factorization.

720145523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1761156.

The product of its (nonzero) digits is 8400, while the sum is 29.

The square root of 720145523 is about 26835.5272539967. The cubic root of 720145523 is about 896.3413292681.

The spelling of 720145523 in words is "seven hundred twenty million, one hundred forty-five thousand, five hundred twenty-three".