87213665 has 32 divisors (see below), whose sum is σ = 131051520. Its totient is φ = 54129600.

The previous prime is 87213647. The next prime is 87213691. The reversal of 87213665 is 56631278.

It is not a de Polignac number, because 87213665 - 2¹² = 87209569 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 137900 + ... + 138530.

It is an arithmetic number, because the mean of its divisors is an integer number (4095360).

Almost surely, 2^87213665 is an apocalyptic number.

It is an amenable number.

87213665 is a deficient number, since it is larger than the sum of its proper divisors (43837855).

87213665 is a wasteful number, since it uses less digits than its factorization.

87213665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1013.

The product of its digits is 60480, while the sum is 38.

The square root of 87213665 is about 9338.8256756404. The cubic root of 87213665 is about 443.4672088324.

It can be divided in two parts, 87213 and 665, that added together give a palindrome (87878).

The spelling of 87213665 in words is "eighty-seven million, two hundred thirteen thousand, six hundred sixty-five".