128649797 has 4 divisors (see below), whose sum is σ = 128681760. Its totient is φ = 128617836.

The previous prime is 128649749. The next prime is 128649803. The reversal of 128649797 is 797946821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 128649797 - 2¹² = 128645701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128649397) 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 in 3 ways as a sum of consecutive naturals, for example, 8897 + ... + 18342.

It is an arithmetic number, because the mean of its divisors is an integer number (32170440).

Almost surely, 2^128649797 is an apocalyptic number.

It is an amenable number.

128649797 is a deficient number, since it is larger than the sum of its proper divisors (31963).

128649797 is an equidigital number, since it uses as much as digits as its factorization.

128649797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31962.

The product of its digits is 1524096, while the sum is 53.

The square root of 128649797 is about 11342.3893867209. The cubic root of 128649797 is about 504.8197860381.

The spelling of 128649797 in words is "one hundred twenty-eight million, six hundred forty-nine thousand, seven hundred ninety-seven".