161660611600 has 30 divisors (see below), whose sum is σ = 388389620330. Its totient is φ = 64664244480.

The previous prime is 161660611591. The next prime is 161660611613. The reversal of 161660611600 is 6116066161.

It can be written as a sum of positive squares in 3 ways, for example, as 21233664 + 161639377936 = 4608^2 + 402044^2 .

It is a super-2 number, since 2×161660611600² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 202075365 + ... + 202076164.

Almost surely, 2^161660611600 is an apocalyptic number.

161660611600 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161660611600 is an abundant number, since it is smaller than the sum of its proper divisors (226729008730).

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

161660611600 is a wasteful number, since it uses less digits than its factorization.

161660611600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404151547 (or 404151536 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 34.

Adding to 161660611600 its reverse (6116066161), we get a palindrome (167776677761).

The spelling of 161660611600 in words is "one hundred sixty-one billion, six hundred sixty million, six hundred eleven thousand, six hundred".