87140521 has 16 divisors (see below), whose sum is σ = 99734544. Its totient is φ = 75423744.

The previous prime is 87140519. The next prime is 87140527. The reversal of 87140521 is 12504178.

It can be written as a sum of positive squares in 8 ways, for example, as 12075625 + 75064896 = 3475^2 + 8664^2 .

It is a cyclic number.

It is not a de Polignac number, because 87140521 - 2¹ = 87140519 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 87140521.

It is not an unprimeable number, because it can be changed into a prime (87140527) 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, 77455 + ... + 78571.

It is an arithmetic number, because the mean of its divisors is an integer number (6233409).

Almost surely, 2^87140521 is an apocalyptic number.

It is an amenable number.

87140521 is a deficient number, since it is larger than the sum of its proper divisors (12594023).

87140521 is a wasteful number, since it uses less digits than its factorization.

87140521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1500.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 87140521 is about 9334.9087301376. The cubic root of 87140521 is about 443.3431990694.

Adding to 87140521 its reverse (12504178), we get a palindrome (99644699).

It can be divided in two parts, 87 and 140521, that added together give a cube (140608 = 52³).

The spelling of 87140521 in words is "eighty-seven million, one hundred forty thousand, five hundred twenty-one".