161785999953 has 24 divisors (see below), whose sum is σ = 243906803712. Its totient is φ = 103144428288.

The previous prime is 161785999943. The next prime is 161785999957. The reversal of 161785999953 is 359999587161.

161785999953 is a `hidden beast` number, since 16 + 17 + 8 + 599 + 9 + 9 + 5 + 3 = 666.

It is not a de Polignac number, because 161785999953 - 2¹⁰ = 161785998929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161785999957) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 847600 + ... + 1020782.

It is an arithmetic number, because the mean of its divisors is an integer number (10162783488).

Almost surely, 2^161785999953 is an apocalyptic number.

It is an amenable number.

161785999953 is a deficient number, since it is larger than the sum of its proper divisors (82120803759).

161785999953 is a wasteful number, since it uses less digits than its factorization.

161785999953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177725 (or 177722 counting only the distinct ones).

The product of its digits is 165337200, while the sum is 72.

The spelling of 161785999953 in words is "one hundred sixty-one billion, seven hundred eighty-five million, nine hundred ninety-nine thousand, nine hundred fifty-three".