1604355749 has 4 divisors (see below), whose sum is σ = 1606587840. Its totient is φ = 1602123660.

The previous prime is 1604355743. The next prime is 1604355761. The reversal of 1604355749 is 9475534061.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1604355749 - 2¹² = 1604351653 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 (1604355743) 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, 1114967 + ... + 1116404.

It is an arithmetic number, because the mean of its divisors is an integer number (401646960).

Almost surely, 2^1604355749 is an apocalyptic number.

It is an amenable number.

1604355749 is a deficient number, since it is larger than the sum of its proper divisors (2232091).

1604355749 is an equidigital number, since it uses as much as digits as its factorization.

1604355749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2232090.

The product of its (nonzero) digits is 453600, while the sum is 44.

The square root of 1604355749 is about 40054.4098570931. The cubic root of 1604355749 is about 1170.6674908912.

The spelling of 1604355749 in words is "one billion, six hundred four million, three hundred fifty-five thousand, seven hundred forty-nine".