87750221 has 16 divisors (see below), whose sum is σ = 99066240. Its totient is φ = 77119680.

The previous prime is 87750217. The next prime is 87750239. The reversal of 87750221 is 12205778.

It is a cyclic number.

It is not a de Polignac number, because 87750221 - 2² = 87750217 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87753221) 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, 79886 + ... + 80976.

It is an arithmetic number, because the mean of its divisors is an integer number (6191640).

Almost surely, 2^87750221 is an apocalyptic number.

It is an amenable number.

87750221 is a deficient number, since it is larger than the sum of its proper divisors (11316019).

87750221 is a wasteful number, since it uses less digits than its factorization.

87750221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1396.

The product of its (nonzero) digits is 7840, while the sum is 32.

The square root of 87750221 is about 9367.5087936975. The cubic root of 87750221 is about 444.3747833159.

Adding to 87750221 its reverse (12205778), we get a palindrome (99955999).

The spelling of 87750221 in words is "eighty-seven million, seven hundred fifty thousand, two hundred twenty-one".