161763921 has 24 divisors (see below), whose sum is σ = 263128320. Its totient is φ = 94874400.

The previous prime is 161763919. The next prime is 161763941. The reversal of 161763921 is 129367161.

161763921 is a `hidden beast` number, since 1 + 6 + 17 + 639 + 2 + 1 = 666.

It is not a de Polignac number, because 161763921 - 2¹ = 161763919 is a prime.

It is a super-2 number, since 2×161763921² = 52335132274588482, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161763941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23286 + ... + 29423.

It is an arithmetic number, because the mean of its divisors is an integer number (10963680).

Almost surely, 2^161763921 is an apocalyptic number.

161763921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

161763921 is a deficient number, since it is larger than the sum of its proper divisors (101364399).

161763921 is a wasteful number, since it uses less digits than its factorization.

161763921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52757 (or 52754 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 161763921 is about 12718.6446211851. The cubic root of 161763921 is about 544.8712441680.

The spelling of 161763921 in words is "one hundred sixty-one million, seven hundred sixty-three thousand, nine hundred twenty-one".