6661121607 has 24 divisors (see below), whose sum is σ = 11119698720. Its totient is φ = 3763584000.

The previous prime is 6661121587. The next prime is 6661121617. The reversal of 6661121607 is 7061211666.

It is not a de Polignac number, because 6661121607 - 2⁸ = 6661121351 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6661121617) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 588394 + ... + 599607.

It is an arithmetic number, because the mean of its divisors is an integer number (463320780).

Almost surely, 2^6661121607 is an apocalyptic number.

6661121607 is a deficient number, since it is larger than the sum of its proper divisors (4458577113).

6661121607 is a wasteful number, since it uses less digits than its factorization.

6661121607 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1188103 (or 1188100 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 6661121607 is about 81615.6946120046. The cubic root of 6661121607 is about 1881.5501029289.

The spelling of 6661121607 in words is "six billion, six hundred sixty-one million, one hundred twenty-one thousand, six hundred seven".