65766556651 has 4 divisors (see below), whose sum is σ = 65774911600. Its totient is φ = 65758201704.

The previous prime is 65766556621. The next prime is 65766556657. The reversal of 65766556651 is 15665566756.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 65766556651 - 2⁹ = 65766556139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65766556657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4165656 + ... + 4181413.

It is an arithmetic number, because the mean of its divisors is an integer number (16443727900).

Almost surely, 2^65766556651 is an apocalyptic number.

65766556651 is a deficient number, since it is larger than the sum of its proper divisors (8354949).

65766556651 is an equidigital number, since it uses as much as digits as its factorization.

65766556651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8354948.

The product of its digits is 34020000, while the sum is 58.

The spelling of 65766556651 in words is "sixty-five billion, seven hundred sixty-six million, five hundred fifty-six thousand, six hundred fifty-one".