164921643 has 32 divisors (see below), whose sum is σ = 254791680. Its totient is φ = 105312960.

The previous prime is 164921633. The next prime is 164921651. The reversal of 164921643 is 346129461.

164921643 is a `hidden beast` number, since 1 + 6 + 4 + 9 + 2 + 1 + 643 = 666.

It is not a de Polignac number, because 164921643 - 2⁵ = 164921611 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 164921598 and 164921607.

It is not an unprimeable number, because it can be changed into a prime (164921623) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 85255 + ... + 87167.

It is an arithmetic number, because the mean of its divisors is an integer number (7962240).

Almost surely, 2^164921643 is an apocalyptic number.

164921643 is a deficient number, since it is larger than the sum of its proper divisors (89870037).

164921643 is a wasteful number, since it uses less digits than its factorization.

164921643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2056 (or 2050 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 164921643 is about 12842.1821743814. The cubic root of 164921643 is about 548.3938186702.

The spelling of 164921643 in words is "one hundred sixty-four million, nine hundred twenty-one thousand, six hundred forty-three".