650128139 has 4 divisors (see below), whose sum is σ = 661147320. Its totient is φ = 639108960.

The previous prime is 650128109. The next prime is 650128151. The reversal of 650128139 is 931821056.

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

It is a cyclic number.

It is not a de Polignac number, because 650128139 - 2¹² = 650124043 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 650128099 and 650128108.

It is not an unprimeable number, because it can be changed into a prime (650128109) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5509502 + ... + 5509619.

It is an arithmetic number, because the mean of its divisors is an integer number (165286830).

Almost surely, 2^650128139 is an apocalyptic number.

650128139 is a deficient number, since it is larger than the sum of its proper divisors (11019181).

650128139 is a wasteful number, since it uses less digits than its factorization.

650128139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11019180.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 650128139 is about 25497.6104566683. The cubic root of 650128139 is about 866.2960241714.

The spelling of 650128139 in words is "six hundred fifty million, one hundred twenty-eight thousand, one hundred thirty-nine".