7216905 has 32 divisors (see below), whose sum is σ = 12063744. Its totient is φ = 3681216.

The previous prime is 7216889. The next prime is 7216919. The reversal of 7216905 is 5096127.

7216905 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 7216905 - 2⁴ = 7216889 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 43132 + ... + 43298.

It is an arithmetic number, because the mean of its divisors is an integer number (376992).

Almost surely, 2^7216905 is an apocalyptic number.

It is an amenable number.

7216905 is a deficient number, since it is larger than the sum of its proper divisors (4846839).

7216905 is a wasteful number, since it uses less digits than its factorization.

7216905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285.

The product of its (nonzero) digits is 3780, while the sum is 30.

The square root of 7216905 is about 2686.4297869105. The cubic root of 7216905 is about 193.2488847060.

It can be divided in two parts, 721 and 6905, that added together give a triangular number (7626 = T₁₂₃).

The spelling of 7216905 in words is "seven million, two hundred sixteen thousand, nine hundred five".