128461666 has 4 divisors (see below), whose sum is σ = 192692502. Its totient is φ = 64230832.

The previous prime is 128461661. The next prime is 128461667. The reversal of 128461666 is 666164821.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 93993025 + 34468641 = 9695^2 + 5871^2 .

It is not an unprimeable number, because it can be changed into a prime (128461661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32115415 + ... + 32115418.

Almost surely, 2^128461666 is an apocalyptic number.

128461666 is a deficient number, since it is larger than the sum of its proper divisors (64230836).

128461666 is an equidigital number, since it uses as much as digits as its factorization.

128461666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64230835.

The product of its digits is 82944, while the sum is 40.

The square root of 128461666 is about 11334.0930823776. The cubic root of 128461666 is about 504.5735916270.

The spelling of 128461666 in words is "one hundred twenty-eight million, four hundred sixty-one thousand, six hundred sixty-six".