87541991 has 2 divisors, whose sum is σ = 87541992. Its totient is φ = 87541990.

The previous prime is 87541957. The next prime is 87541997. The reversal of 87541991 is 19914578.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 87541991 - 2¹⁸ = 87279847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87541997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43770995 + 43770996.

It is an arithmetic number, because the mean of its divisors is an integer number (43770996).

Almost surely, 2^87541991 is an apocalyptic number.

87541991 is a deficient number, since it is larger than the sum of its proper divisors (1).

87541991 is an equidigital number, since it uses as much as digits as its factorization.

87541991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 44.

The square root of 87541991 is about 9356.3877110774. The cubic root of 87541991 is about 444.0230066130.

The spelling of 87541991 in words is "eighty-seven million, five hundred forty-one thousand, nine hundred ninety-one".