161700009975 has 72 divisors (see below), whose sum is σ = 333604044800. Its totient is φ = 73337866560.

The previous prime is 161700009971. The next prime is 161700010009. The reversal of 161700009975 is 579900007161.

It is not a de Polignac number, because 161700009975 - 2² = 161700009971 is a prime.

It is a super-2 number, since 2×161700009975² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 161700009975.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161700009971) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 204175 + ... + 604224.

Almost surely, 2^161700009975 is an apocalyptic number.

161700009975 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

161700009975 is an abundant number, since it is smaller than the sum of its proper divisors (171904034825).

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

161700009975 is a wasteful number, since it uses less digits than its factorization.

161700009975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 808549 (or 808541 counting only the distinct ones).

The product of its (nonzero) digits is 119070, while the sum is 45.

The spelling of 161700009975 in words is "one hundred sixty-one billion, seven hundred million, nine thousand, nine hundred seventy-five".