146639721 has 16 divisors (see below), whose sum is σ = 201369600. Its totient is φ = 94877328.

The previous prime is 146639707. The next prime is 146639723. The reversal of 146639721 is 127936641.

It is not a de Polignac number, because 146639721 - 2²¹ = 144542569 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 146639721.

It is not an unprimeable number, because it can be changed into a prime (146639723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8740 + ... + 19226.

It is an arithmetic number, because the mean of its divisors is an integer number (12585600).

Almost surely, 2^146639721 is an apocalyptic number.

It is an amenable number.

146639721 is a deficient number, since it is larger than the sum of its proper divisors (54729879).

146639721 is a wasteful number, since it uses less digits than its factorization.

146639721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10628.

The product of its digits is 54432, while the sum is 39.

The square root of 146639721 is about 12109.4888826903. The cubic root of 146639721 is about 527.3316950688.

The spelling of 146639721 in words is "one hundred forty-six million, six hundred thirty-nine thousand, seven hundred twenty-one".