661266633465 has 32 divisors (see below), whose sum is σ = 1186571928960. Its totient is φ = 349379497152.

The previous prime is 661266633463. The next prime is 661266633473. The reversal of 661266633465 is 564336662166.

It is a happy number.

661266633465 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 661266633465 - 2¹ = 661266633463 is a prime.

It is a super-3 number, since 3×661266633465³ (a number of 36 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (661266633463) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22874674 + ... + 22903563.

It is an arithmetic number, because the mean of its divisors is an integer number (37080372780).

Almost surely, 2^661266633465 is an apocalyptic number.

It is an amenable number.

661266633465 is a deficient number, since it is larger than the sum of its proper divisors (525305295495).

661266633465 is a wasteful number, since it uses less digits than its factorization.

661266633465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45778358 (or 45778352 counting only the distinct ones).

The product of its digits is 16796160, while the sum is 54.

The spelling of 661266633465 in words is "six hundred sixty-one billion, two hundred sixty-six million, six hundred thirty-three thousand, four hundred sixty-five".