161641641 has 48 divisors (see below), whose sum is σ = 260751744. Its totient is φ = 88736256.

The previous prime is 161641633. The next prime is 161641681. The reversal of 161641641 is 146146161.

It is not a de Polignac number, because 161641641 - 2³ = 161641633 is a prime.

It is a super-2 number, since 2×161641641² = 52256040210345762, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161641599 and 161641608.

It is not an unprimeable number, because it can be changed into a prime (161641681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 614476 + ... + 614738.

It is an arithmetic number, because the mean of its divisors is an integer number (5432328).

Almost surely, 2^161641641 is an apocalyptic number.

It is an amenable number.

161641641 is a deficient number, since it is larger than the sum of its proper divisors (99110103).

161641641 is a wasteful number, since it uses less digits than its factorization.

161641641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430 (or 423 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The square root of 161641641 is about 12713.8365964016. The cubic root of 161641641 is about 544.7339171907.

The spelling of 161641641 in words is "one hundred sixty-one million, six hundred forty-one thousand, six hundred forty-one".