87656491 has 4 divisors (see below), whose sum is σ = 94399312. Its totient is φ = 80913672.

The previous prime is 87656467. The next prime is 87656497. The reversal of 87656491 is 19465678.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19465678 = 2 ⋅9732839.

It is a cyclic number.

It is not a de Polignac number, because 87656491 - 2¹³ = 87648299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87656497) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3371391 + ... + 3371416.

It is an arithmetic number, because the mean of its divisors is an integer number (23599828).

Almost surely, 2^87656491 is an apocalyptic number.

87656491 is a deficient number, since it is larger than the sum of its proper divisors (6742821).

87656491 is a wasteful number, since it uses less digits than its factorization.

87656491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6742820.

The product of its digits is 362880, while the sum is 46.

The square root of 87656491 is about 9362.5045260336. The cubic root of 87656491 is about 444.2165079800.

The spelling of 87656491 in words is "eighty-seven million, six hundred fifty-six thousand, four hundred ninety-one".