1605065644 has 48 divisors (see below), whose sum is σ = 3537495808. Its totient is φ = 620198208.

The previous prime is 1605065633. The next prime is 1605065647. The reversal of 1605065644 is 4465605061.

It is not an unprimeable number, because it can be changed into a prime (1605065647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35622 + ... + 66925.

Almost surely, 2^1605065644 is an apocalyptic number.

1605065644 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1605065644 is an abundant number, since it is smaller than the sum of its proper divisors (1932430164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1605065644 is a wasteful number, since it uses less digits than its factorization.

1605065644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102614 (or 102612 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 37.

The square root of 1605065644 is about 40063.2705105312. The cubic root of 1605065644 is about 1170.8401310002.

The spelling of 1605065644 in words is "one billion, six hundred five million, sixty-five thousand, six hundred forty-four".