1601601616 has 20 divisors (see below), whose sum is σ = 3106652724. Its totient is φ = 799884800.

The previous prime is 1601601613. The next prime is 1601601623. The reversal of 1601601616 is 6161061061.

It can be written as a sum of positive squares in 2 ways, for example, as 518928400 + 1082673216 = 22780^2 + 32904^2 .

It is a super-2 number, since 2×1601601616² = 5130255472747622912, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1601601611) 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, 42715 + ... + 70906.

Almost surely, 2^1601601616 is an apocalyptic number.

1601601616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1601601616 is a deficient number, since it is larger than the sum of its proper divisors (1505051108).

1601601616 is a wasteful number, since it uses less digits than its factorization.

1601601616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114510 (or 114504 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1601601616 is about 40020.0151924009. The cubic root of 1601601616 is about 1169.9972279380.

Adding to 1601601616 its reverse (6161061061), we get a palindrome (7762662677).

The spelling of 1601601616 in words is "one billion, six hundred one million, six hundred one thousand, six hundred sixteen".