66601625749 has 8 divisors (see below), whose sum is σ = 68023998720. Its totient is φ = 65179474416.

The previous prime is 66601625729. The next prime is 66601625759. The reversal of 66601625749 is 94752610666.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66601625749 - 2¹⁹ = 66601101461 is a prime.

It is a super-2 number, since 2×66601625749² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66601625696 and 66601625705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66601625729) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 645667 + ... + 741679.

It is an arithmetic number, because the mean of its divisors is an integer number (8502999840).

Almost surely, 2^66601625749 is an apocalyptic number.

It is an amenable number.

66601625749 is a deficient number, since it is larger than the sum of its proper divisors (1422372971).

66601625749 is a wasteful number, since it uses less digits than its factorization.

66601625749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110819.

The product of its (nonzero) digits is 3265920, while the sum is 52.

The spelling of 66601625749 in words is "sixty-six billion, six hundred one million, six hundred twenty-five thousand, seven hundred forty-nine".