161654403616 has 12 divisors (see below), whose sum is σ = 318257107182. Its totient is φ = 80827201792.

The previous prime is 161654403593. The next prime is 161654403623. The reversal of 161654403616 is 616304456161.

It can be written as a sum of positive squares in only one way, i.e., 153805152400 + 7849251216 = 392180^2 + 88596^2 .

It is a super-2 number, since 2×161654403616² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2525850025 + ... + 2525850088.

Almost surely, 2^161654403616 is an apocalyptic number.

161654403616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

161654403616 is a deficient number, since it is larger than the sum of its proper divisors (156602703566).

161654403616 is an equidigital number, since it uses as much as digits as its factorization.

161654403616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5051700123 (or 5051700115 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 43.

Adding to 161654403616 its reverse (616304456161), we get a palindrome (777958859777).

The spelling of 161654403616 in words is "one hundred sixty-one billion, six hundred fifty-four million, four hundred three thousand, six hundred sixteen".