87983989 has 2 divisors, whose sum is σ = 87983990. Its totient is φ = 87983988.

The previous prime is 87983971. The next prime is 87984011. The reversal of 87983989 is 98938978.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 87048900 + 935089 = 9330^2 + 967^2 .

It is a cyclic number.

It is not a de Polignac number, because 87983989 - 2⁵ = 87983957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87983969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43991994 + 43991995.

It is an arithmetic number, because the mean of its divisors is an integer number (43991995).

Almost surely, 2^87983989 is an apocalyptic number.

It is an amenable number.

87983989 is a deficient number, since it is larger than the sum of its proper divisors (1).

87983989 is an equidigital number, since it uses as much as digits as its factorization.

87983989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7838208, while the sum is 61.

The square root of 87983989 is about 9379.9780916588. The cubic root of 87983989 is about 444.7690406101.

The spelling of 87983989 in words is "eighty-seven million, nine hundred eighty-three thousand, nine hundred eighty-nine".