66687651 has 16 divisors (see below), whose sum is σ = 104608800. Its totient is φ = 41842944.

The previous prime is 66687637. The next prime is 66687667. The reversal of 66687651 is 15678666.

It is not a de Polignac number, because 66687651 - 2⁵ = 66687619 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66687597 and 66687606.

It is not an unprimeable number, because it can be changed into a prime (66687671) 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, 72186 + ... + 73103.

It is an arithmetic number, because the mean of its divisors is an integer number (6538050).

Almost surely, 2^66687651 is an apocalyptic number.

66687651 is a deficient number, since it is larger than the sum of its proper divisors (37921149).

66687651 is a wasteful number, since it uses less digits than its factorization.

66687651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145315 (or 145309 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 66687651 is about 8166.2507309046. The cubic root of 66687651 is about 405.5226722266.

The spelling of 66687651 in words is "sixty-six million, six hundred eighty-seven thousand, six hundred fifty-one".