87289421 has 2 divisors, whose sum is σ = 87289422. Its totient is φ = 87289420.

The previous prime is 87289381. The next prime is 87289429. The reversal of 87289421 is 12498278.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 84088900 + 3200521 = 9170^2 + 1789^2 .

It is a cyclic number.

It is not a de Polignac number, because 87289421 - 2¹⁴ = 87273037 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87289429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43644710 + 43644711.

It is an arithmetic number, because the mean of its divisors is an integer number (43644711).

Almost surely, 2^87289421 is an apocalyptic number.

It is an amenable number.

87289421 is a deficient number, since it is larger than the sum of its proper divisors (1).

87289421 is an equidigital number, since it uses as much as digits as its factorization.

87289421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64512, while the sum is 41.

The square root of 87289421 is about 9342.8807655883. The cubic root of 87289421 is about 443.5955739585.

The spelling of 87289421 in words is "eighty-seven million, two hundred eighty-nine thousand, four hundred twenty-one".