164888721 has 24 divisors (see below), whose sum is σ = 249000960. Its totient is φ = 105019200.

The previous prime is 164888719. The next prime is 164888743. The reversal of 164888721 is 127888461.

It is not a de Polignac number, because 164888721 - 2¹ = 164888719 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (164888701) 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, 18301 + ... + 25781.

It is an arithmetic number, because the mean of its divisors is an integer number (10375040).

Almost surely, 2^164888721 is an apocalyptic number.

It is an amenable number.

164888721 is a deficient number, since it is larger than the sum of its proper divisors (84112239).

164888721 is a wasteful number, since it uses less digits than its factorization.

164888721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7597 (or 7594 counting only the distinct ones).

The product of its digits is 172032, while the sum is 45.

The square root of 164888721 is about 12840.9003189029. The cubic root of 164888721 is about 548.3573257385.

The spelling of 164888721 in words is "one hundred sixty-four million, eight hundred eighty-eight thousand, seven hundred twenty-one".