87158381 has 2 divisors, whose sum is σ = 87158382. Its totient is φ = 87158380.

The previous prime is 87158359. The next prime is 87158387. The reversal of 87158381 is 18385178.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74978281 + 12180100 = 8659^2 + 3490^2 .

It is a cyclic number.

It is not a de Polignac number, because 87158381 - 2⁶ = 87158317 is a prime.

It is a super-2 number, since 2×87158381² = 15193166757082322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87158387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43579190 + 43579191.

It is an arithmetic number, because the mean of its divisors is an integer number (43579191).

Almost surely, 2^87158381 is an apocalyptic number.

It is an amenable number.

87158381 is a deficient number, since it is larger than the sum of its proper divisors (1).

87158381 is an equidigital number, since it uses as much as digits as its factorization.

87158381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 41.

The square root of 87158381 is about 9335.8653053694. The cubic root of 87158381 is about 443.3734856630.

The spelling of 87158381 in words is "eighty-seven million, one hundred fifty-eight thousand, three hundred eighty-one".