128697220 has 12 divisors (see below), whose sum is σ = 270264204. Its totient is φ = 51478880.

The previous prime is 128697199. The next prime is 128697223. The reversal of 128697220 is 22796821.

It can be written as a sum of positive squares in 2 ways, for example, as 95726656 + 32970564 = 9784^2 + 5742^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 128697220.

It is not an unprimeable number, because it can be changed into a prime (128697223) 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, 3217411 + ... + 3217450.

It is an arithmetic number, because the mean of its divisors is an integer number (22522017).

Almost surely, 2^128697220 is an apocalyptic number.

128697220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

128697220 is an abundant number, since it is smaller than the sum of its proper divisors (141566984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128697220 is a wasteful number, since it uses less digits than its factorization.

128697220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6434870 (or 6434868 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 128697220 is about 11344.4797148217. The cubic root of 128697220 is about 504.8818074540.

The spelling of 128697220 in words is "one hundred twenty-eight million, six hundred ninety-seven thousand, two hundred twenty".