66202249681 has 4 divisors (see below), whose sum is σ = 66217900864. Its totient is φ = 66186598500.

The previous prime is 66202249679. The next prime is 66202249723. The reversal of 66202249681 is 18694220266.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66202249681 - 2¹ = 66202249679 is a prime.

It is a super-2 number, since 2×66202249681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66202249601) 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, 7819245 + ... + 7827706.

It is an arithmetic number, because the mean of its divisors is an integer number (16554475216).

Almost surely, 2^66202249681 is an apocalyptic number.

It is an amenable number.

66202249681 is a deficient number, since it is larger than the sum of its proper divisors (15651183).

66202249681 is a wasteful number, since it uses less digits than its factorization.

66202249681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15651182.

The product of its (nonzero) digits is 497664, while the sum is 46.

The spelling of 66202249681 in words is "sixty-six billion, two hundred two million, two hundred forty-nine thousand, six hundred eighty-one".