87766531 has 4 divisors (see below), whose sum is σ = 89633952. Its totient is φ = 85899112.

The previous prime is 87766517. The next prime is 87766537. The reversal of 87766531 is 13566778.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 87766531 - 2¹¹ = 87764483 is a prime.

It is a super-2 number, since 2×87766531² = 15405927927547922, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (87766537) 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 3 ways as a sum of consecutive naturals, for example, 933640 + ... + 933733.

It is an arithmetic number, because the mean of its divisors is an integer number (22408488).

Almost surely, 2^87766531 is an apocalyptic number.

87766531 is a deficient number, since it is larger than the sum of its proper divisors (1867421).

87766531 is a wasteful number, since it uses less digits than its factorization.

87766531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1867420.

The product of its digits is 211680, while the sum is 43.

The square root of 87766531 is about 9368.3793155487. The cubic root of 87766531 is about 444.4023133651.

The spelling of 87766531 in words is "eighty-seven million, seven hundred sixty-six thousand, five hundred thirty-one".