400280405 has 16 divisors (see below), whose sum is σ = 549659520. Its totient is φ = 274126272.

The previous prime is 400280399. The next prime is 400280423. The reversal of 400280405 is 504082004.

It is not a de Polignac number, because 400280405 - 2⁸ = 400280149 is a prime.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 22031 + ... + 35859.

It is an arithmetic number, because the mean of its divisors is an integer number (34353720).

Almost surely, 2^400280405 is an apocalyptic number.

It is an amenable number.

400280405 is a deficient number, since it is larger than the sum of its proper divisors (149379115).

400280405 is a wasteful number, since it uses less digits than its factorization.

400280405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14668.

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 400280405 is about 20007.0088968841. The cubic root of 400280405 is about 736.9784296547.

The spelling of 400280405 in words is "four hundred million, two hundred eighty thousand, four hundred five".