400857709 has 8 divisors (see below), whose sum is σ = 466767360. Its totient is φ = 337109136.

The previous prime is 400857707. The next prime is 400857727. The reversal of 400857709 is 907758004.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 400857709 - 2¹ = 400857707 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 (400857701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 539869 + ... + 540610.

It is an arithmetic number, because the mean of its divisors is an integer number (58345920).

Almost surely, 2^400857709 is an apocalyptic number.

It is an amenable number.

400857709 is a deficient number, since it is larger than the sum of its proper divisors (65909651).

400857709 is a wasteful number, since it uses less digits than its factorization.

400857709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1080539.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 400857709 is about 20021.4312425461. The cubic root of 400857709 is about 737.3325615863.

The spelling of 400857709 in words is "four hundred million, eight hundred fifty-seven thousand, seven hundred nine".