87240665 has 16 divisors (see below), whose sum is σ = 108504576. Its totient is φ = 67267200.

The previous prime is 87240563. The next prime is 87240667. The reversal of 87240665 is 56604278.

It is a happy number.

It is not a de Polignac number, because 87240665 - 2²⁶ = 20131801 is a prime.

It is a super-3 number, since 3×87240665³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (87240667) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42554 + ... + 44556.

It is an arithmetic number, because the mean of its divisors is an integer number (6781536).

Almost surely, 2^87240665 is an apocalyptic number.

It is an amenable number.

87240665 is a deficient number, since it is larger than the sum of its proper divisors (21263911).

87240665 is a wasteful number, since it uses less digits than its factorization.

87240665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2320.

The product of its (nonzero) digits is 80640, while the sum is 38.

The square root of 87240665 is about 9340.2711416746. The cubic root of 87240665 is about 443.5129676373.

The spelling of 87240665 in words is "eighty-seven million, two hundred forty thousand, six hundred sixty-five".