161764867809 has 24 divisors (see below), whose sum is σ = 246893549760. Its totient is φ = 101778787872.

The previous prime is 161764867807. The next prime is 161764867861. The reversal of 161764867809 is 908768467161.

161764867809 is a `hidden beast` number, since 1 + 6 + 1 + 76 + 486 + 7 + 80 + 9 = 666.

It is not a de Polignac number, because 161764867809 - 2¹ = 161764867807 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161764867807) 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, 1753494 + ... + 1843439.

It is an arithmetic number, because the mean of its divisors is an integer number (10287231240).

Almost surely, 2^161764867809 is an apocalyptic number.

161764867809 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

161764867809 is a deficient number, since it is larger than the sum of its proper divisors (85128681951).

161764867809 is a wasteful number, since it uses less digits than its factorization.

161764867809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3597221 (or 3597218 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 63.

The spelling of 161764867809 in words is "one hundred sixty-one billion, seven hundred sixty-four million, eight hundred sixty-seven thousand, eight hundred nine".