1605631113 has 48 divisors (see below), whose sum is σ = 2538423360. Its totient is φ = 1002857472.

The previous prime is 1605631103. The next prime is 1605631151. The reversal of 1605631113 is 3111365061.

1605631113 is a `hidden beast` number, since 16 + 0 + 5 + 631 + 1 + 13 = 666.

It is not a de Polignac number, because 1605631113 - 2⁸ = 1605630857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1605631103) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2707345 + ... + 2707937.

It is an arithmetic number, because the mean of its divisors is an integer number (52883820).

Almost surely, 2^1605631113 is an apocalyptic number.

It is an amenable number.

1605631113 is a deficient number, since it is larger than the sum of its proper divisors (932792247).

1605631113 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (1605631112) it forms an eRAP, since the sums of their prime factors are consecutive (982 and 983).

1605631113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 983 (or 960 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 1605631113 is about 40070.3270887573. The cubic root of 1605631113 is about 1170.9776115794.

Adding to 1605631113 its reverse (3111365061), we get a palindrome (4716996174).

The spelling of 1605631113 in words is "one billion, six hundred five million, six hundred thirty-one thousand, one hundred thirteen".