87133621 has 2 divisors, whose sum is σ = 87133622. Its totient is φ = 87133620.

The previous prime is 87133597. The next prime is 87133633. The reversal of 87133621 is 12633178.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43758225 + 43375396 = 6615^2 + 6586^2 .

It is a cyclic number.

It is not a de Polignac number, because 87133621 - 2⁵ = 87133589 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87131621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43566810 + 43566811.

It is an arithmetic number, because the mean of its divisors is an integer number (43566811).

Almost surely, 2^87133621 is an apocalyptic number.

It is an amenable number.

87133621 is a deficient number, since it is larger than the sum of its proper divisors (1).

87133621 is an equidigital number, since it uses as much as digits as its factorization.

87133621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 31.

The square root of 87133621 is about 9334.5391423466. The cubic root of 87133621 is about 443.3314970935.

Adding to 87133621 its reverse (12633178), we get a palindrome (99766799).

The spelling of 87133621 in words is "eighty-seven million, one hundred thirty-three thousand, six hundred twenty-one".