87666431 has 4 divisors (see below), whose sum is σ = 90035832. Its totient is φ = 85297032.

The previous prime is 87666413. The next prime is 87666443. The reversal of 87666431 is 13466678.

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 87666431 - 2¹⁴ = 87650047 is a prime.

It is a super-2 number, since 2×87666431² = 15370806248555522, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87666451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1184645 + ... + 1184718.

It is an arithmetic number, because the mean of its divisors is an integer number (22508958).

Almost surely, 2^87666431 is an apocalyptic number.

87666431 is a deficient number, since it is larger than the sum of its proper divisors (2369401).

87666431 is a wasteful number, since it uses less digits than its factorization.

87666431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2369400.

The product of its digits is 145152, while the sum is 41.

The square root of 87666431 is about 9363.0353518504. The cubic root of 87666431 is about 444.2332983136.

The spelling of 87666431 in words is "eighty-seven million, six hundred sixty-six thousand, four hundred thirty-one".