128492785 has 4 divisors (see below), whose sum is σ = 154191348. Its totient is φ = 102794224.

The previous prime is 128492773. The next prime is 128492803. The reversal of 128492785 is 587294821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 587294821 = 37 ⋅15872833.

It can be written as a sum of positive squares in 2 ways, for example, as 38489616 + 90003169 = 6204^2 + 9487^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128492785 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12849274 + ... + 12849283.

It is an arithmetic number, because the mean of its divisors is an integer number (38547837).

Almost surely, 2^128492785 is an apocalyptic number.

It is an amenable number.

128492785 is a deficient number, since it is larger than the sum of its proper divisors (25698563).

128492785 is an equidigital number, since it uses as much as digits as its factorization.

128492785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25698562.

The product of its digits is 322560, while the sum is 46.

The square root of 128492785 is about 11335.4658042799. The cubic root of 128492785 is about 504.6143315571.

The spelling of 128492785 in words is "one hundred twenty-eight million, four hundred ninety-two thousand, seven hundred eighty-five".