76521665 has 16 divisors (see below), whose sum is σ = 102067776. Its totient is φ = 54600000.

The previous prime is 76521659. The next prime is 76521673. The reversal of 76521665 is 56612567.

It is not a de Polignac number, because 76521665 - 2¹⁰ = 76520641 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10211 + ... + 16040.

It is an arithmetic number, because the mean of its divisors is an integer number (6379236).

Almost surely, 2^76521665 is an apocalyptic number.

It is an amenable number.

76521665 is a deficient number, since it is larger than the sum of its proper divisors (25546111).

76521665 is a wasteful number, since it uses less digits than its factorization.

76521665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26320.

The product of its digits is 75600, while the sum is 38.

The square root of 76521665 is about 8747.6662602091. Note that the first 3 decimals coincide. The cubic root of 76521665 is about 424.5493076983.

The spelling of 76521665 in words is "seventy-six million, five hundred twenty-one thousand, six hundred sixty-five".