400790509 has 4 divisors (see below), whose sum is σ = 458046304. Its totient is φ = 343534716.

The previous prime is 400790501. The next prime is 400790531. The reversal of 400790509 is 905097004.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 400790509 - 2³ = 400790501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400790501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28627887 + ... + 28627900.

It is an arithmetic number, because the mean of its divisors is an integer number (114511576).

Almost surely, 2^400790509 is an apocalyptic number.

It is an amenable number.

400790509 is a deficient number, since it is larger than the sum of its proper divisors (57255795).

400790509 is an equidigital number, since it uses as much as digits as its factorization.

400790509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57255794.

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 400790509 is about 20019.7529705039. The cubic root of 400790509 is about 737.2913570091.

The spelling of 400790509 in words is "four hundred million, seven hundred ninety thousand, five hundred nine".