400109785 has 4 divisors (see below), whose sum is σ = 480131748. Its totient is φ = 320087824.

The previous prime is 400109767. The next prime is 400109791. The reversal of 400109785 is 587901004.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 52809289 + 347300496 = 7267^2 + 18636^2 .

It is a cyclic number.

It is not a de Polignac number, because 400109785 - 2²¹ = 398012633 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 400109785.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40010974 + ... + 40010983.

It is an arithmetic number, because the mean of its divisors is an integer number (120032937).

Almost surely, 2^400109785 is an apocalyptic number.

It is an amenable number.

400109785 is a deficient number, since it is larger than the sum of its proper divisors (80021963).

400109785 is an equidigital number, since it uses as much as digits as its factorization.

400109785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80021962.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 400109785 is about 20002.7444367017. The cubic root of 400109785 is about 736.8737021283.

The spelling of 400109785 in words is "four hundred million, one hundred nine thousand, seven hundred eighty-five".