87217540 has 24 divisors (see below), whose sum is σ = 184974552. Its totient is φ = 34540800.

The previous prime is 87217513. The next prime is 87217567. The reversal of 87217540 is 4571278.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (87217513) and next prime (87217567).

It can be written as a sum of positive squares in 4 ways, for example, as 33547264 + 53670276 = 5792^2 + 7326^2 .

It is a junction number, because it is equal to n+sod(n) for n = 87217496 and 87217505.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19569 + ... + 23608.

It is an arithmetic number, because the mean of its divisors is an integer number (7707273).

Almost surely, 2^87217540 is an apocalyptic number.

It is an amenable number.

87217540 is an abundant number, since it is smaller than the sum of its proper divisors (97757012).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87217540 is a wasteful number, since it uses less digits than its factorization.

87217540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43287 (or 43285 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 87217540 is about 9339.0331405344. The cubic root of 87217540 is about 443.4737766487.

It can be divided in two parts, 8721 and 7540, that added together give a palindrome (16261).

The spelling of 87217540 in words is "eighty-seven million, two hundred seventeen thousand, five hundred forty".