72684021 has 16 divisors (see below), whose sum is σ = 101965248. Its totient is φ = 45993600.

The previous prime is 72683999. The next prime is 72684037. The reversal of 72684021 is 12048627.

It is not a de Polignac number, because 72684021 - 2⁹ = 72683509 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 72684021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72684091) 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 15 ways as a sum of consecutive naturals, for example, 3435 + ... + 12536.

It is an arithmetic number, because the mean of its divisors is an integer number (6372828).

Almost surely, 2^72684021 is an apocalyptic number.

It is an amenable number.

72684021 is a deficient number, since it is larger than the sum of its proper divisors (29281227).

72684021 is a wasteful number, since it uses less digits than its factorization.

72684021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16052.

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 72684021 is about 8525.4924197961. The cubic root of 72684021 is about 417.3300413789.

The spelling of 72684021 in words is "seventy-two million, six hundred eighty-four thousand, twenty-one".