161201639997 has 32 divisors (see below), whose sum is σ = 251254066560. Its totient is φ = 102012877440.

The previous prime is 161201639971. The next prime is 161201640037. The reversal of 161201639997 is 799936102161.

161201639997 is a `hidden beast` number, since 1 + 612 + 0 + 16 + 3 + 9 + 9 + 9 + 7 = 666.

161201639997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 161201639997 - 2⁶ = 161201639933 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161201639917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1926883 + ... + 2008800.

It is an arithmetic number, because the mean of its divisors is an integer number (7851689580).

Almost surely, 2^161201639997 is an apocalyptic number.

It is an amenable number.

161201639997 is a deficient number, since it is larger than the sum of its proper divisors (90052426563).

161201639997 is a wasteful number, since it uses less digits than its factorization.

161201639997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3935770 (or 3935764 counting only the distinct ones).

The product of its (nonzero) digits is 1102248, while the sum is 54.

The spelling of 161201639997 in words is "one hundred sixty-one billion, two hundred one million, six hundred thirty-nine thousand, nine hundred ninety-seven".