661328167 has 2 divisors, whose sum is σ = 661328168. Its totient is φ = 661328166.

The previous prime is 661328153. The next prime is 661328189. The reversal of 661328167 is 761823166.

It is a happy number.

661328167 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661328167 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661398167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330664083 + 330664084.

It is an arithmetic number, because the mean of its divisors is an integer number (330664084).

Almost surely, 2^661328167 is an apocalyptic number.

661328167 is a deficient number, since it is larger than the sum of its proper divisors (1).

661328167 is an equidigital number, since it uses as much as digits as its factorization.

661328167 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 72576, while the sum is 40.

The square root of 661328167 is about 25716.3015809039. The cubic root of 661328167 is about 871.2424082191.

The spelling of 661328167 in words is "six hundred sixty-one million, three hundred twenty-eight thousand, one hundred sixty-seven".