72785121 has 4 divisors (see below), whose sum is σ = 97046832. Its totient is φ = 48523412.

The previous prime is 72785101. The next prime is 72785191. The reversal of 72785121 is 12158727.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 72785121 - 2¹⁰ = 72784097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72785101) 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 3 ways as a sum of consecutive naturals, for example, 12130851 + ... + 12130856.

It is an arithmetic number, because the mean of its divisors is an integer number (24261708).

Almost surely, 2^72785121 is an apocalyptic number.

It is an amenable number.

72785121 is a deficient number, since it is larger than the sum of its proper divisors (24261711).

72785121 is a wasteful number, since it uses less digits than its factorization.

72785121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24261710.

The product of its digits is 7840, while the sum is 33.

The square root of 72785121 is about 8531.4196356761. The cubic root of 72785121 is about 417.5234471156.

The spelling of 72785121 in words is "seventy-two million, seven hundred eighty-five thousand, one hundred twenty-one".