87491811 has 16 divisors (see below), whose sum is σ = 131650560. Its totient is φ = 51196320.

The previous prime is 87491779. The next prime is 87491819. The reversal of 87491811 is 11819478.

It is not a de Polignac number, because 87491811 - 2⁵ = 87491779 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 87491811.

It is not an unprimeable number, because it can be changed into a prime (87491819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44755 + ... + 46668.

It is an arithmetic number, because the mean of its divisors is an integer number (8228160).

Almost surely, 2^87491811 is an apocalyptic number.

87491811 is a deficient number, since it is larger than the sum of its proper divisors (44158749).

87491811 is a wasteful number, since it uses less digits than its factorization.

87491811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91466.

The product of its digits is 16128, while the sum is 39.

The square root of 87491811 is about 9353.7057362310. The cubic root of 87491811 is about 443.9381508280.

The spelling of 87491811 in words is "eighty-seven million, four hundred ninety-one thousand, eight hundred eleven".