221612087 has 16 divisors (see below), whose sum is σ = 234399744. Its totient is φ = 209244000.

The previous prime is 221612077. The next prime is 221612089. The reversal of 221612087 is 780216122.

221612087 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 221612087 - 2¹⁶ = 221546551 is a prime.

It is a super-3 number, since 3×221612087³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221612089) 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, 235037 + ... + 235977.

It is an arithmetic number, because the mean of its divisors is an integer number (14649984).

Almost surely, 2^221612087 is an apocalyptic number.

221612087 is a deficient number, since it is larger than the sum of its proper divisors (12787657).

221612087 is a wasteful number, since it uses less digits than its factorization.

221612087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1150.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 221612087 is about 14886.6412262807. The cubic root of 221612087 is about 605.1520115260.

The spelling of 221612087 in words is "two hundred twenty-one million, six hundred twelve thousand, eighty-seven".