661289467 has 2 divisors, whose sum is σ = 661289468. Its totient is φ = 661289466.

The previous prime is 661289437. The next prime is 661289543. The reversal of 661289467 is 764982166.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661289467 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 661289467.

It is not a weakly prime, because it can be changed into another prime (661289417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330644733 + 330644734.

It is an arithmetic number, because the mean of its divisors is an integer number (330644734).

Almost surely, 2^661289467 is an apocalyptic number.

661289467 is a deficient number, since it is larger than the sum of its proper divisors (1).

661289467 is an equidigital number, since it uses as much as digits as its factorization.

661289467 is an evil number, because the sum of its binary digits is even.

The product of its digits is 870912, while the sum is 49.

The square root of 661289467 is about 25715.5491288831. The cubic root of 661289467 is about 871.2254132583.

The spelling of 661289467 in words is "six hundred sixty-one million, two hundred eighty-nine thousand, four hundred sixty-seven".