66613633 has 12 divisors (see below), whose sum is σ = 72114300. Its totient is φ = 61498112.

The previous prime is 66613627. The next prime is 66613649. The reversal of 66613633 is 33631666.

66613633 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 565504 + 66048129 = 752^2 + 8127^2 .

It is a de Polignac number, because none of the positive numbers 2^k-66613633 is a prime.

It is a super-2 number, since 2×66613633² = 8874752202917378, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (66613693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13143 + ... + 17491.

It is an arithmetic number, because the mean of its divisors is an integer number (6009525).

Almost surely, 2^66613633 is an apocalyptic number.

It is an amenable number.

66613633 is a deficient number, since it is larger than the sum of its proper divisors (5500667).

66613633 is a wasteful number, since it uses less digits than its factorization.

66613633 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4436 (or 4419 counting only the distinct ones).

The product of its digits is 34992, while the sum is 34.

The square root of 66613633 is about 8161.7175275796. The cubic root of 66613633 is about 405.3725840235.

The spelling of 66613633 in words is "sixty-six million, six hundred thirteen thousand, six hundred thirty-three".