87538221 has 6 divisors (see below), whose sum is σ = 126444110. Its totient is φ = 58358808.

The previous prime is 87538177. The next prime is 87538229. The reversal of 87538221 is 12283578.

It can be written as a sum of positive squares in only one way, i.e., 83064996 + 4473225 = 9114^2 + 2115^2 .

It is not a de Polignac number, because 87538221 - 2¹³ = 87530029 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87538229) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4863226 + ... + 4863243.

Almost surely, 2^87538221 is an apocalyptic number.

It is an amenable number.

87538221 is a deficient number, since it is larger than the sum of its proper divisors (38905889).

87538221 is a wasteful number, since it uses less digits than its factorization.

87538221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9726475 (or 9726472 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 87538221 is about 9356.1862422677. The cubic root of 87538221 is about 444.0166325642.

The spelling of 87538221 in words is "eighty-seven million, five hundred thirty-eight thousand, two hundred twenty-one".