405020523 has 4 divisors (see below), whose sum is σ = 540027368. Its totient is φ = 270013680.

The previous prime is 405020519. The next prime is 405020531. The reversal of 405020523 is 325020504.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 405020523 - 2² = 405020519 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 405020523.

It is not an unprimeable number, because it can be changed into a prime (405020513) 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, 67503418 + ... + 67503423.

It is an arithmetic number, because the mean of its divisors is an integer number (135006842).

Almost surely, 2^405020523 is an apocalyptic number.

405020523 is a deficient number, since it is larger than the sum of its proper divisors (135006845).

405020523 is a wasteful number, since it uses less digits than its factorization.

405020523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135006844.

The product of its (nonzero) digits is 1200, while the sum is 21.

The square root of 405020523 is about 20125.1216890731. The cubic root of 405020523 is about 739.8761193894.

The spelling of 405020523 in words is "four hundred five million, twenty thousand, five hundred twenty-three".