131601616 has 10 divisors (see below), whose sum is σ = 254978162. Its totient is φ = 65800800.

The previous prime is 131601611. The next prime is 131601643. The reversal of 131601616 is 616106131.

It can be written as a sum of positive squares in only one way, i.e., 72250000 + 59351616 = 8500^2 + 7704^2 .

It is a super-2 number, since 2×131601616² = 34637970667622912, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131601611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4112535 + ... + 4112566.

Almost surely, 2^131601616 is an apocalyptic number.

131601616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

131601616 is a deficient number, since it is larger than the sum of its proper divisors (123376546).

131601616 is an equidigital number, since it uses as much as digits as its factorization.

131601616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8225109 (or 8225103 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 131601616 is about 11471.7747537162. The cubic root of 131601616 is about 508.6515911777.

Adding to 131601616 its reverse (616106131), we get a palindrome (747707747).

The spelling of 131601616 in words is "one hundred thirty-one million, six hundred one thousand, six hundred sixteen".