10400645 has 4 divisors (see below), whose sum is σ = 12480780. Its totient is φ = 8320512.

The previous prime is 10400641. The next prime is 10400659. The reversal of 10400645 is 54600401.

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 1833316 + 8567329 = 1354^2 + 2927^2 .

It is a cyclic number.

It is not a de Polignac number, because 10400645 - 2² = 10400641 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10400641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1040060 + ... + 1040069.

It is an arithmetic number, because the mean of its divisors is an integer number (3120195).

Almost surely, 2^10400645 is an apocalyptic number.

It is an amenable number.

10400645 is a deficient number, since it is larger than the sum of its proper divisors (2080135).

10400645 is an equidigital number, since it uses as much as digits as its factorization.

10400645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2080134.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 10400645 is about 3225.0031007737. The cubic root of 10400645 is about 218.2830890087.

Subtracting from 10400645 its sum of digits (20), we obtain a square (10400625 = 3225²).

It can be divided in two parts, 104006 and 45, that multiplied together give a triangular number (4680270 = T₃₀₅₉).

The spelling of 10400645 in words is "ten million, four hundred thousand, six hundred forty-five".