1404643657 has 4 divisors (see below), whose sum is σ = 1420426260. Its totient is φ = 1388861056.

The previous prime is 1404643637. The next prime is 1404643661. The reversal of 1404643657 is 7563464041.

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 130439241 + 1274204416 = 11421^2 + 35696^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1404643657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1404643627) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7891168 + ... + 7891345.

It is an arithmetic number, because the mean of its divisors is an integer number (355106565).

Almost surely, 2^1404643657 is an apocalyptic number.

It is an amenable number.

1404643657 is a deficient number, since it is larger than the sum of its proper divisors (15782603).

1404643657 is an equidigital number, since it uses as much as digits as its factorization.

1404643657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15782602.

The product of its (nonzero) digits is 241920, while the sum is 40.

The square root of 1404643657 is about 37478.5759734812. The cubic root of 1404643657 is about 1119.9244360691.

The spelling of 1404643657 in words is "one billion, four hundred four million, six hundred forty-three thousand, six hundred fifty-seven".