66261457633 has 32 divisors (see below), whose sum is σ = 79468849152. Its totient is φ = 54060048000.

The previous prime is 66261457601. The next prime is 66261457637. The reversal of 66261457633 is 33675416266.

It is not a de Polignac number, because 66261457633 - 2⁵ = 66261457601 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66261457637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13115958 + ... + 13121008.

It is an arithmetic number, because the mean of its divisors is an integer number (2483401536).

Almost surely, 2^66261457633 is an apocalyptic number.

It is an amenable number.

66261457633 is a deficient number, since it is larger than the sum of its proper divisors (13207391519).

66261457633 is a wasteful number, since it uses less digits than its factorization.

66261457633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6205.

The product of its digits is 3265920, while the sum is 49.

The spelling of 66261457633 in words is "sixty-six billion, two hundred sixty-one million, four hundred fifty-seven thousand, six hundred thirty-three".