1605897949 has 4 divisors (see below), whose sum is σ = 1611061920. Its totient is φ = 1600733980.

The previous prime is 1605897919. The next prime is 1605898097. The reversal of 1605897949 is 9497985061.

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 1605897949 - 2⁹ = 1605897437 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1605897893 and 1605897902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1605897919) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 2581519 + ... + 2582140.

It is an arithmetic number, because the mean of its divisors is an integer number (402765480).

Almost surely, 2^1605897949 is an apocalyptic number.

It is an amenable number.

1605897949 is a deficient number, since it is larger than the sum of its proper divisors (5163971).

1605897949 is an equidigital number, since it uses as much as digits as its factorization.

1605897949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5163970.

The product of its (nonzero) digits is 4898880, while the sum is 58.

The square root of 1605897949 is about 40073.6565464146. The cubic root of 1605897949 is about 1171.0424753105.

The spelling of 1605897949 in words is "one billion, six hundred five million, eight hundred ninety-seven thousand, nine hundred forty-nine".